I don't believe you are worthless. I think you are just going thru a hard time right now. College is so different from high school and that first year of college is a big adjustment. Add to that depression and anxiety disorder and it is just rough. Rather than dropping out of college altogether, maybe you may want to drop the class that is problematic and take it later. Don't be afraid to see a college counselor for help. You will probably find that they are very familiar with the type of problem you are having and could give you some helpful advice. Take a deep breath, think things thru.

I went thru some of the stuff you are dealing with when I was 18 and I was in college. I got scared and dropped out of school, but now looking back I wish I had stayed in and just changed my major. It really is easier to go to college when you are younger. An education gives you more choices and opportunities in life. You sound like you are too bright to throw in the towel completely. Don't let one class mess you up. You are going to do fine down the road.