No interest in life. But it's too much.

I feel sad all the time. I have anxiety and sometimes my heart beats so fast that I feel like I'll faint. I was a brilliant student but now, I don't care about academics at all. I have terrible mood swings. I feel okay only when I am making plans that I know I won't follow through or buying things. I can't read or watch movies or listen to music because it seems like too much work. I don't pick up phone calls because it also feels like a lot of work. I feel tired all the time. I am vegan. I take multivitamin and B12 everyday. I don't eat mostly but sometimes I'll eat till it hurts. I feel like I don't have emotions but Sometimes I feel like sobbing for no reason. I was always an introvert. I have felt this way since I was 13. I could ignore it and focus on something else back then but I haven't been able to do that for the last five years. I also have a habit of self diagnosing so I thought I had depression and anxiety disorder and I have been trying to cure myself but it's too much.