As the title suggests, during my own private practice time, after playing for awhile, my left shoulder/arm begins to tense up immensely to the point where I can barely stand to keep the horn up and continue playing. Has anybody had any experience with something similar? As a little back story, starting out in high school, I never had a private instructor so I was self taught for the most part, outside of generalized teaching my band director gave during class, (his primary is the French horn, so I never really got a lot of good advice from him). Anyways, since I never had any true guidance in my developmental stages, I substituted good air support with good old fashion, lip bleeding pressure on my top lip to produce what I wanted to produce, (though, in retrospect, I don't think I ever truly produced what I wanted, anyway...hmm.). Do you guys think the tensing of my arm/shoulder is in any way correlated to my bad habits growing up, (I'd like to put on record that pressure is no longer an issue, or rather, as much of an issue ), and if you guys know of any methods to relieve this tension?.. Or should I start looking for my health insurance card?