Good BP can be achieved by short people... Look at Dani Pedrosa. He's 5'2" and MotoGP bikes aren't exactly tiny.
Also, IMHO knee on the back corner of the tank isn't bad... it's good. Here's a pic of Pol Espargaro, knee barely on the edge of the tank.
It might be that it feels odd to really hang off. I think I'm WAY off the bike and pics show I'm really not.
Your BP looks darned good, especially for a first track day!
Food for thought: Most of your mass is in your upper body (more for men than women, but still true). Your head alone weighs as much as a watermelon. So the more you get your upper body off, the less lean angle the bike will have.
Look at the pic a few posts back of csmith12 following me. We look pretty similar overall... but focus in on the right shoulder. See how his is centered in the windscreen, and mine is still over the right clip-on? His body is about six inches farther off the bike than mine is.
I don't know how much of a difference that makes, but I can say this... I have yet to touch a knee down.