I'm in high school and a teenager, so I can't fully understand your situation, but you are telling me that you dropped out of college because you had a poor presentation. I definitely understand the annoyance and aggravation that stuttering can cause to its beholder, but don't give up on university, or any dream you have, because of it. That is very very drastic, and you might regret in the future not getting a degree because of your stutter, or worse, because of one bad presentation. You have probably heard this before, but your stuttering does not define you! You are saying that you have improved from constant stuttering to it becoming random. That is improvement. Your control is definite. Please don't feel discouraged so much to the point of making this kind of a change in life. There is a movie, The King's Speech. The therapist, Lionel Logue, says "every stammerers fear is to go back to square one". I think based off of your post, you feel this way. Do not sweat it! It is just another step in getting ultimately over the stutter!