depression, stress, school, life

I always say to myself and others that I'm going to do well in school, when i fail a test, I say I'll get back up, but always end up screwing up and procrastinating. Then I start comparing myself to others who have passed and doing well, and yet I say to myself that, that's nothing and that its easy for me to do that too. Then later on, I do bad, procrastinate, I eat a lot now, barely get exercise done. I feel so weak every time I am studying especially the night before the test. My body's beginning to feel so weak. Please tell me whats going on, because I wouldn't ask a question like this on here if I knew. help me.. On top of all the stress in school, i feel a bit pressured from everyone. I came from a family that thinks I'm doing very well, because Ive been showing them I've been doing good. Thinking about that makes me so mad at myself, because instead of doing what I'm suppose to, i do something else, my time managing is getting out of control, getting to the point where feel so down. I find myself in weird positions with friends too. every time they would talk about, doing bad in school and family problems and what not, i give them advice that would solve it, but yet, i can't get myself to believe my own advice. I feel like Im saying it, but I'm not doing it, because i feel like its easy to be done, but never is.Am I a hypocrite? ..ughh If this continues any longer I really don't know what's going to happen. Please help me.