Hello everyone. I have been on a very demanding and extensive playing schedule since I have been at a summer music program. This includes much more practice than I am used to. My lips are doing OK. My playing is getting more consistent when I rest for long enough. But, for some unknown reason, I have been sort of biting my bottom lip when I play high. A really painful sore has developed on the corner of my lip, and it limits my range because it just hurts like heck. Any suggestions that don't include not playing at all? I am open to anything else. Thanks a lot!