Why am I doing this?

If I know I'm not going to come back, why one last time?

Anxiety?

I don't want my professor to think that I gave up and didn't try. I just can't handle this. I'm torn between calling it quits, or persevering knowing I will fail. I think that my life has always been dictated by how I feel and what I understand about myself. 

I know that, in a half a semester, I cannot fully be able to understand or have enough time to study these things and keep my head above water. I have a ton of other things I need to fulfill. I want to focus on getting my writing under control. I don't think I can stay normal and understand all of anatomy and chemistry and the variation between vertebrates in just a month while creating a project and doing RA things and trying to improve my writing.

What I'm being taught is so interesting, but I know I don't have enough prior knowledge or time to understand it all. There is so much information hit at me in this class in so little time, I can't possibly understand everything given to me in a class period. So I am at the point where I am ignoring it. The amount of terms are so vast in just one part of the small intestine, that I can't understand. 

I just can't continue it. And it makes me sad that I know this class is my last, but I'm doing this for me this time. It doesn't hinder me in any way. I need to fully understand the things I have in my other classes because they are important for me to keep going.