Newb Having Trouble with Needs

I'm new to Sims (thank you SO much for this website!), and I started playing earlier today.
I hope this is the right place to ask this--but how do you balance needs? I understand the concept, but it's really hard for me.
My Sim is a diva who lives in Bridgeport with her "non-destructive" dog. I have hardly been able to do ANYTHING because their needs are constantly low. They get tired VERY easily...for example, after a full night of rest (though she did get up at 5 am), she got exhausted at the leisure festival by 3 pm. Her dog seems to constantly need to destroy things (though she hasn't touched the furniture), but my Sim hates the noise of the squeaky toy. Her dog also gets hungry pretty fast
She hasn't been able to go look for a job because I can't balance her and her dog's needs. Once my Sim even slept through a visit from an acquaintance. XD (The acquaintance had to play with the dog, and she woke up just as the person was leaving.)
Is this normal? I'm seriously considering using cheats to turn off the needs.
I saw a Let's Play and the needs certainly didn't bother that person too much.

Hello! I may be new to the site(though I have been floating around for a few months), but I've been playing The Sims 3 for over a year.

Balancing needs can be hard. First, double check that your sims have high free will. (Click Options, then on Game Options tab there is a Free Will slider. Slide it all the way to the right.). If High Free Will is on, Sims will automaticaly run around and take care of themselves unless you cancel their actions. If the sim gets tired, she'll run to bed or get a cup of coffee. Granted, you may already have this on and are still struggling.

My suggestion is to purchase a coffee maker from Buy Mode(Under Appliances click the Small Appliances tab). Every time she drinks from this she will get a 3 hour energy boost. I use this very often when my sims are tired but have friends over.

For longer term restfulness, pick one sim day where all they will do is sleep. Make sure they have eaten a lot and used the bathroom before doing this as they most likely will get hungry and need to pee while sleeping. Early in the morning click on any bed, then click sleep. When the action appears at the top, click and drag the small lined bar on the right side of the action. This will extend the amount of time they sleep for. If the sim gets up at anytime during the day, return them to bed and pull the side of the action tab again. After a full day of sleep, they should have a full energy bar and you should be able to put them to sleep at a decent hour and manage to have a full energy bar when they wake up.(Double check on the Needs tab.).

Now have them go about their sim day. Around 9 or 10 at night, send them to bed. Have them sleep until they are full rested. But if they get up before 8 hours have passed, then they might get tired too early.

As for the dog, put it's toys in a seperate room, or outside. Lock the door to this area when the dog is inside by clicking on the door and selecting Lock. To unlock, click the door again and select Unlock. This way the dog can fulfill it's destruction need while not annyoing your sim. If you need any more help or if I've missed anything, just ask!

Thank you for your reply--I can try that.
The only problem is that I live in Bridgeport and don't have a lot of space, so my dog has to be in the same room as my Sim.

If you live in an Apartment in Bridgeport I can see the difficulties with that... If you want to make your apartment bigger I can suggest somework arounds. However, they are cheats. Press Ctrl+Shift+C and the command bar will appear at the top. In the bar, type testingcheatsenabled true. Press Enter. The press Ctrl+Shift+C again and type restrictbuildbuyinbuildings off. Press Enter. Now in Build Mode you should be able to drag the walls of your apartment into the dark areas of the floor. A little orb may appear in the public areas and the dark areas. Leave the Public Orb alone. Move the Hidden Orb away from where you want to build but do not delete it and do not put it in your apartment. Leave a little bit of dark space near a door to the public area(that door is where Service Sims go to fulfill their needs. Deleting all doors can cause glitching, so I always leave one with some dark space and the Hidden Orb behind it.).

An alternative without cheats is maybe only have your dog use the toy while your Sim is out of the house? Send your Sim out for dinner or to a night club and leave the dog at home. Make sure it chews on the toy the whole time your Sim is gone.

I think I'm going to try to play with minimal cheats, but thanks for the tip anyways. I haven't been able to try your tips yet, but I do remember now that the bench in the park by my apartment is able to be chewed. I don't know if there are consequences, though.
I could try sending my Sim out to a nightclub, too. (It would certainly help with her social needs--considering I made her a social-loving gal).

I'll probably try to get her sleeping pattern right, though, instead of coffee...I've given her coffee before and she always gets the "caffiene crash" moodlet a little while later. It doesn't seem to help her energy significantly, either.

One funny thing that starts happening when her needs are low is that she'll go into the bathroom (that has no mirror) and starts complimenting herself. XD I think it's a diva thing...

Yeah, coffee is just an emergency thing for my Sims. Someone pops over and my Sim is exhausted? Serve Hot drinks! But yeah, just getting the Sim into a sleeping pattern is really helpful. As for the doggy, I'm not finding any 'consequences' for destroying said bench, other than the bench may break. So that's a great idea, unless you have an undying love for that bench, XD. Also, maybe you could drop your dog off in the dog park with his Chew toy? Place a Dog park or build one of your own (preferably near your apartment) with public chew toys and destructable furniture.

And wow... I have not seen a Sim do that before! I've seen Insane Sims just plain talking to themselves, but not checking themselves out or complimenting themselves without a mirror. I love how this game has all these little surprises, even after playing so long.

I've started to get the hang of needs--thanks for the advice. (I also tried out the nraas mod Relativity, and it helps me play at a slower pace)

And, yeah, I just love finding surprises in the Sims. I do believe it's her diva trait, though. She compliments herself when her social motive is low, as I found. She can even ask others for compliments, though it's a little off-putting to others.