In a few short words:
You are breathing with your lower rib cage compressing the air. Stop doing that.
Do it this way:
As you inhale push your stomach out.
Hold your breath this way for a fraction of a second to get the feel of it.
Pressurize the air stream with the upper band of abdominal muscles.
Start low in the staff and scale up while increasing the air, tongue level and upper lip contraction. You will have a lot to work on, take a lot of time. Get an exercise book to guide you.
If you contract your upper lip muscle too soon and too hard you can tear the muscle. It will end your career.
One way we were shown how to breath was to sit in a chair. Take in a lot of air down deep with the gut pushed out. Bend over and point your trumpet at the floor and play. The only way you can get the air out is using your abdominals. This was from Michael Tunnell.
Mike Tunnell Trumpet Studio > School of Music > University of Louisville
Get this book at Hicky's music: Progressive studies in the High Register. Keith Johnson.
Hickeys Music Center - Trumpet Studies & Etudes It is only $10.00 I really like it. I have been playing it every day.