To the OP, disregard the vid I posted, although to a degree if you "stop it," it might help.
I suggest you change your grip. Personally, I don't hold my trumpet in the traditional left hand grip anymore, where you hold the horn with the 3rd finger through the ring and all fingers around the casings above the 3rd valve slide. I split the grip, two fingers above, two fingers below the 3rd valve slide, with the tip of my middle finger through the ring. For me it's just as effective as the normal grip, and in some ways I think is a better grip than the traditional grip.
One thing that seems to ring true, for almost any serious musician I have known or read about, particularly drummers, at some point along the way some changes had to be made due to the occupational injuries caused by the repetition of playing the instrument. Carpel tunnel syndrome is the most common, but shoulder and knee pain, back issues, neck issues, etc - there are so many things that can arise from the repletion of playing a musical instrument.
Changes have ranged from everything to better, more ergonomic approaches, in the cases of drummers, sometimes it's repositioning drums and cymbals to different heights and locations, working on posture, doing yoga, and in some cases, simply backing off of the amount of time spent practicing, all in an effort to keep from further aggravating an injury.
I once went through a thing with one of the knuckles on the middle finger of my left hand - an issue that cropped up one night playing drums for a praise band rehearsal. I don't know if it was how I was hitting the snare that night or what, but that inflammatory injury persisted for months until I made a point to ask to be taken out of the rotation for a bit, and I simply stopped playing drums altogether for about 5-6 weeks. It finally went away on its own, and fortunately has never returned.
Keep us posted with what you wind up doing.