I can relate, I'm 20 and I've been struggling with a bucket-load of problems similar to you.
I've always had a problem doing homework, or convincing myself to do anything that wasn't immediately pleasing to me. I've always been restless, which has been exacerbated by my eczema and scalp dermatitis, which has caused me to develop a skin-picking disorder that's been haunting me daily... hourly for... about 5 years now. I've had the hardest time with education and retaining anything I've learned... that is if I could keep myself paying attention long enough to learn anything.. I don't even feel like I can process thinking anymore.. I feel like I'm just simply reacting to everything.. at one point I was a relaxed and chill kid, now I feel just socially awkward and totally down about life...
I would advise you talk to someone, it's important to deal with these problems before they worsen. I feel for you, and you aren't alone.
One possibility is to get someone from your high school to talk with your mother. Main point being how grades, etc. will improve. High school counselor is probably the best bet, although sometimes teachers will also be willing. Might want to look into special ed testing because if you qualify you can get more time for tests, etc. If you don't qualify, you could get a 405 Plan instead which would also give you more time on tests. All of these your counselor should be able to help with. Good Luck