What the heck

Legit, I just dont understand anymore. How is it that I love science, want to be a vet major, and cant understand anything that comes out of this mans mouth. I study all week for an exam and THIS is all I get? I just dont understand! My life is over! Once I get a C my GPA is going to be terrible, and Ill never get into med school, and ill not become who i feel i am supposed to be! This is bad....how am i going to be a bio major when i cant even get a B in a class that is my major... Maybe im not cut out for this and i should just go work at Target for the rest of my life and pay off my loans....God you better show me what i have to do to get better grades next year or im never going to get to vet school.....