Working and going to school with fibromyalgia?

Hello guys! Im 17, and im getting to the point where im tired of spending my mothers money. The most I'll spend at any given time is around 25 dollars on her debit card, and I very rarely will go over that because I know my mother works hard to earn her money. My mother has never told me to get up and get a job because she knows I have fibro, and doesnt want me to over-exert myself, but I feel so guilty spending her money. I mainly get cute clothes(especially for spring and summer), shoes(again, very rarely over 20-15 dollars) and im getting into makeup and things of that nature(what girl doesn't love a nice eyeshadow? lol)...Those are not necessities, so I want to get a job so I can buy what I want with my own money. I just want to be a little bit more independent when it comes to money(I mean, I cook for myself, wake myself up in the morning, do my laundry, even make my own doctors appointments when my mother cant come with me)
Thing is, im afraid to get a job because I dont know how I would be able to physically handle it, and if I'd be able to keep it.. Going to school everyday is kinda difficult, and I dont wanna have too much on my plate by working and being exhausted all of the time. How do you guys handle it?

Edit: It seems like a lot of kids my age have jobs and are buying their own things, and I feel incredibly lazy compared to them :( If I didnt have fibro, I would have gotten a job a longgggg time ago....

Momof2nSC, as long as I dont have to be on my feet for too long, I'd love to work in a restaurant :)
I know for a fact that I wanna get a summer job, I just have to get my working papers in order...when I start college this fall, I'll see if I can adjust my work schedule accordingly...
(side note: I also have Raynauds...I get it from my mom)

I totally understand where you're coming from. I really respect and applaud you for not wanting to "mooch" off your parents like a lot of kids do. But I wouldn't classify what you're doing as mooching.

How are your grades? Maybe you could tutor middle school or elementary school kids, especially over the summer. Does your high school have any programs that could get you an internship over the summer?

If those things don't work, maybe you could look into different ways to make money online or from home. Some telemarketing companies let people make phone calls from home.