I have two mini bruises on the lower lip on the outer surface of the lower lip that goes inside the MP rim. While I don't play trumpet they almost disappear but after a practice session they become prominent: two small prominent blue bruises less but close to 1 mm in diameter that are a little off the lip center. I didn't touch a trumpet MP for 1 month recently and they almost disappeared (in fact they disappear in 10 minutes after any practice session) but when I started to play trumpet again they poped up. Is this a common trumpet playing lip problem or am I lucky ? I n fact I don't know when they first appeared, it could be a leftover from my clarinet or saxophone playing.