This is something you might ask one of the adults who is overseeing this school event about. You could explain that you need to take medication and have a desire for a certain amount of privacy and how will that be arranged? Perhaps you could buddy up with one of the shyer students. I would be very surprised if you are the only person who takes medications and many people like and need a certain amount of privacy. And finally, as much as people like to gather in groups and find a common ground, common interests, and belong (and that's a good thing) all people are individuals and special in their own ways, and that's a good thing, too. Have fun.