Grades and stress :( Please Help Me?

Ok well midterms is coming up for me and ive been wondering...Im an all A student and i overstress myself to maintain that A. Especially towards midterms and final is when i wanna just jump off a cliff instead of deal with this stress. But my question is, is it ok if i get a B on my report card? Like do you think i would eventually get a B in my life.?