I had some of the same issues a few years ago when I picked up the trumpet after a 25yr hiatus. The problem wasn't my embouchure it was a lack of practice. My warm up would wear me out!!! My suggestion would be a regimen of long tones. In have logged countless hours on my hose trumpet doing long tones. When I concentrated on what I was doing while playing long tones (talking @ your embouchure), I figured out what worked and what didn't. I subscribe to the "rubber face embouchure" method (Dale Clevenger). Too many variables with an individual IMO to pigeon - hole into just a handful of "proper" methods. Also don't subscribe to the 5 year plan to see if it works pedagogical mindset. To some that's heresy but I figure YOLO!!!!! It has worked well for me these last 8 years! Now go do the right thing (longtones)!