Nope, you're not losing your mind
. I actually wrote a post a few days back about
this. I am going throught the same thing. My chest x-ray and PFT came back absolutely normal. The three different doctors I saw are chalking it up to the humidity. It is scary though - the sensation of not getting enough air.
A couple things that help me out are:
1. Limiting caffeine (since it enhances the side-effects of the breathing meds I'm taking)
2. Taking my breathing meds at the EXACT same time every day.
I'll admit, my breathing isn't perfect (even with the meds), but it makes things a lot more bearable.
Good luck!