I think school is slowly killing me

I'm not going to do it but sometimes I feel like if I don't get a 3.0 GPA, then there's no point in living. I know it sounds so dumb but school (my school anyways) is always making seem like only the most competitive people live life. And while I constantly try to get to 3.0, something in my always wants to stay in bed and stare at the ceiling and think about what I could've done better. Somehow I manage to get out of bed and into classes but then there's something that keeps me from engaging. I'll be in the class and I'm completely aware of what's going on, but otherwise I'm suck thinking thoughts about how I could've done better it I couldn't do it. I do pray myself to do better but so far I've just been becoming more numb and sullen. Does anyone else feel this way or understand what's happening to me? I was never like this but I don't know that happened.