You are not a failure. Have you failed at something? Quite possibly. Failure at an activity/task does not make you personally a failure. You actually tried to do something that's hard for you. There are so many people in this world that don't.

Have you tried talking to your prof?

(I also have a truly abysmal time with math, to the point I dropped math not once, but three times in college and barely scraped through Logic to fulfill my math requirement.)