Chris,
Happy Birthday and congrats on the new job.
You're stressed out because you're a teenager, and being a teenager is stressful. I'm not going to get on your case about that, ok? But, I'd like to discuss some of the points you raised in your post.
I'm sure you know how fortunate you are that you and your family don't experience money troubles. That is a whole other kind of stress that I think would completely eclipse the "stresses" you're feeling now. But I really hope you never learn that first hand!
When I was your age (insert crochety old-lady voice here; btw, I'm closing in on my 30th birthday), honestly, these things weren't even an issue. Your generation is dealing with this techo-lust for the first time, and you've got to navigate your way through these waters. The way you're spending (or asking your folks to spend for you) is not realistic for someone with an average income. If you are going to be a serious high-earner as an adult, be my guest in buying ten cell phones in two years! But until that time, you might want to practice a little more restraint in your spending habits. You'll be glad you did, in the future.
I had a really nice little nest-egg when I got out of college from saving up my money, and it helped me to get some of the things that actually become more important when you're an adult (car, utilities, housing, insurance, etc.). Right now, the only thing you as a 15 y/o have to spend money on are *luxury items.* This all changes when you're an adult.
I don't want you to turn out like one of those kids who goes to college and gets into monstrous amounts of debt because you take four credit card offers from the student center. Go into debt because you have student loans, if you have to, not because you buy things you don't need. And if you're going to continue to be blessed with inordinate sums of cash from your "rich" family, be grateful that you won't have to worry about your retirement or what might happen to you if you incur excessive medical bills.
Okay, I'm off to go lament my leaky roof and buy long-term care insurance.

Maybe not exactly, but you get my drift?
Be well,
MM