Am I worrying too much?

I go to an extremely challenging college, and this semester has especially been a ride. It doesn’t help that I came back from a year off.

This semester I had a paper for each of my four classes and I have gotten three back. Two of them were liked and nicely graded, but today I got the third which I will confess I didn’t put as much effort into and was for a class which I had (and am having) difficultly with. I apparently didn’t fully understand the subject and while the note is somewhat reassuring I feel defeated. It was the first paper before I changed my method, I have drastically improved in that class and talked to my tutor. I am also a sophomore, and there’s nothing indicating I have trouble with scholarships or anything.

I know this is probably not that big of a deal, but getting the paper back set off my anxiety and I feel depressed because I know I could have done much better. I know I should remember what I can work on and move forward (or currently enjoy the upcoming break) but I can’t. Am I worrying too much? If so, how do I let this go?