Stressed!!!!!

So pretty much this year has been pretty stressful, i have to make sure i do well on my ACT and i am so scared, i don't really know why. I have this feeling like i don't think i will be able to graduate, and i'm scared. I hate it when people are like "oh my gosh i got my first B how terrible." sorry but that is just weird! anyways i wish i could say that actually then i wouldn't be stressed over if i am going to graduate or not. I don't know what to do.