I've been doing some Bill Adams daily routine stuff every night, I've been practicing in front of a mirror and drinking water and all sorts of stuff to get better and be a more serious player, and I've noticed some things. When I start running out of air in lip slurs (or in general for that matter) my neck starts getting more tense and some veins stick out a little. They start becoming visible when I'm about halfway empty of air, and it only happens when I'm playing above middle C. If I'm playing low tones it doesn't really happen. So my main question is, is a little neck tension going to hurt? And should my neck look the exact same if I'm not playing, or if I'm playing low G's or high C's?