I started trading sophomore year in college and am doing it full time now after graduation. I probably spent about 3-4 hours trading everyday and still had plenty of time left over for having fun and hanging out with friends. I don't know what your college environment is like but depending on what you major in college in the US can be a cakewalk. Open an account and start trading. You will find out soon enough if you are a natural trader. If you can make serious cash then trading is for you. Otherwise let it go and pursue a real career.
I am a 3rd year student at university of toronto. Traded last year, didn't make money, quit. Starting again very soon bcuz I know a lot more now. God knows if I'll make money or close up the broker account again.