I did a week-long residential course at UMIST in Manchester as part of A103. I was nervous going on my own, but went because I had to, and when I completed the week, I was so glad I had gone.
Basically, I had a room (single) in the Halls, which was nice, and food was included - we'd get vouchers up to a certain value. You get there and register, and are given a time table and venues, so you know where to go, which puts you at ease. The group I was in was probably no more than 20 people, with whom I was with all week. We had seminar style lessons, and even watched a movie in the lecture theatre! Being in a small group, we made friends pretty quickly, and had to do some group work to do a presentation at the end of the week, which was fine, as you really will have broken the ice by then!
I would say go. It's a really good experience, and presentations are over and done with in no time. If it is a group one, you won't be speaking all of the time, and can perhaps negotiate with the others, so you speak less. Anyhow, a presentation is good experience, as some job interviews expect this now.
Hope you get on well with your course. Good luck!