Mark, you're on the right track and definitely doing the kinds of things that keep a person striving for that next thing, whether it's cleaning up the articulation a bit, working through a difficult passage you couldn't quite hit the week before, noticing that your tone is more open and full that it was before....all of that kind of stuff is the kind of intrinsic rewards that keeps that musician's fire burning.
The recording - man, I can't say enough about that. I must have listened to that little ditty I put together with multiple trumpet tracks and drums 50+ times today on my way too and from work! I was really stoked about how it turned out and as always, it forced a level of concentration and focus that brought my whole game up - no doubt it will do the same for you.
Not sure about that collaboration effort though - you just have to be sure that the other guy isn't some major yo-yo.
As for your teacher, he'll know in a few more months that you are in it to stay, and you could be doing some performances soon too. Once you take your solo act and join up with some other musicians, you'll be more hooked than ever!
Just keep on keepin' on, and keep us updated on your progress - inquiring minds want to know after all!