Well, it's good you can self-analyze like that. I think everyone goes through something of a journey with stuttering and other problems. I tried drinking before college classes too. What helped me was coming to the realization that stuttering literally can't kill me. It could be humiliating, but it couldn't kill me. So what is there to fear? Either I'm dead or I'm not, and if I'm not I'll just keep going, no matter how much it hurts. Eventually, it starts to hurt less and less. I wish you luck! You've got a lot more to do in the world than worry about and try to hide your stutter. One life to live.