For years, my biggest problem with playing in general was pinching my lips to the point that they were stiff as boards. I've also run into issues where while "playing hard" I would tear the outer layer of skin on my upper lip on the right side. It started happening in high school and has plagued me for years.
What I noticed (after years of self abuse) was that when my lips were stiffened to play in the upper register, they would lose the elasticity and eventually tear under the immense strain from the vibration. Kind of like a rubber band being stretched to its maximum length while someone strums or "twangs" it. They eventually snap!
Here's the fix - it's a change in habit, so the first few times takes mindful practice... by relaxing your lips and allowing them to vibrate in balance with your airstream vs. adding tension and not increasing the amount of air. Most brass players tend to pinch their lips to increase the range vs. push more air. If we can turn that around, we can play with greater efficiency, sound, power, and ultimately - control!