I have a young trumpet player (about grade 3, aged 13) who has been complaining of the side of his face aching when playing. It also looks slightly swollen to me today. The main area is at the back of his cheek, just above the jaw line. Any ideas what would have caused this? He has a brace, but he tells me that their are no cuts or ulcers in his mouth in this area. He warms up and warms down properly at the start of the lesson. We were not playing high notes (D on the fourth line) and he'd only been playing for 15 minutes. I've never had a pupil complain of this problem before - has anyone else encountered this? I have suggested he takes a few days break from playing, and we'll take it from there. Any ideas?