Miguel,
As John Elwood said, “Welcome!” Mr. Elwood gives good advice.
I believe you are rushing your progress to no progress. I had to start the Largo stage three times before I realized how to translate WindWorks into playing. Check out John’s and my posts to the thread “I Smile As I Play”.
You need to spend much time practicing the fundamentals: concert hall breath and AAH-OOH embouchure with the visualizer, then mouthpiece, and leadpipe. Since I am assuming you have no gigs or any performances, I would suggest you play beginning material using only this method; otherwise, you will be reinforcing old habits. Those that have playing engagements have to apply the “two houses” analogy.
I know what you are talking about when you mentioned air pockets. These usually form when the player is overblowing. Trying to force too much air through a small opening and air often forces pockets to form above the lips, sometimes below. It is more common as you ascend to higher or play loudly or both.
If you follow Greg’s program without rushing through, eventually you should be able to play softly above the staff or loudly with a beautiful tone at any volume without pockets, pinched lips, rolling lips, or excessive pressure anywhere (abdominal or mouthpiece).
Bottom line: practice those fundamentals until they become automatic. Proceed to exercise in the Largo Singing C, continuing to practice the fundamentals and do not rush the Largo Singing C exercises.
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