Then if anything debating will help you overcome your fears. You will be presenting in a safe environment with friends you know. I have not once encountered or heard, at UDS or tournaments, anybody being judged for having a hard time presenting, and if we ever did, we would quickly deal with any agitators. We debaters all had to start from the bottom, all had a blackout at one point and all understand that it takes time. I’ve even gone up against a debater with a stutter once, who may or may not have annihilated me.
If we still haven’t convinced you on that, you can still judge a couple of debates before trying it yourself. It’s without the debating but all the judging. Judges are just as important, even sometimes more so than debaters. Good judges are always in short supply and you can make a name for yourself in the debating community through judging.