The first time I played trumpet and once when I played it after not having played it for a while the part of my lips that fit inside the mouthpiece ended up forming a puffy lip circle while the rest of my lips stayed normal.

Once I was sitting on a folding chair with a tuba between my legs on the folding chair when I dropped it on the floor and the bell slammed me in the lips as it fell, but it didn't leave a mark and it was a one-time thing.