I don’t know what to do anymore.

I’ll be 16 in 2 weeks. Sometimes I just hate myself so so much. I’m stupid, disappointing and I feel alone. I’m currently laying in bed crying imagining killing myself. My marks r bad. I’m disappointing my parents and I don’t think I’m going to go anywhere in life. My 2 best friends im pretty sure they’d choose each other over me and they’re also way smarter than me. They always make jokes every time I say something dumb. I have a bf and a lot of the time I’m on the fence about our relationship. I just feel like no one cares and that I feel so alone and filled w sadness. Sometimes I’ll feel like this for a week and it’ll go away for a little while and then it’s like something will trigger it again and I’ll be back to feeling sad and angry at myself for being the way I am. Normally when I get like this I’ll scratch at my wrist but I’ve been trying to stop. All of this is so embarrassing cz I sound like such a messed up person:( I just don’t know what to do anymore.