Originally Posted by BowlenBall
On a more serious note, the reason you're having a crisis of confidence is because it's difficult and you're challenging yourself. Dig deep and work harder, that's what higher education's all about.
Create a positive reinforcement cycle. Tell yourself you can do it, that you just need to work harder, then do it, then see the good results, cycle and repeat. If you should have a rough stretch, know that it's not because you aren't adequate but that you just need to work harder. It's really as simple as that!