I'm An 18-year-old Going Into College With A Major In

I'm an 18-year-old going into college with a major in classical vocal performance. However, I have a slight problem that's bothering me.
I've never been fond of singing high notes due to my constant specialty of cracking above the staff. However, I've discovered that my voice cracks only between an F and G, above and below those two notes my voice is fine (although, above a G my voice automatically switches into head voice). Is this just a register break or something else?
Something else that might be relevant is that my wisdom teeth are coming out, and also my jaw clicks when I open and close it (any solutions for the click?)

Thank you very much!