I recently had 3 rehearsal schedules going on at once (2 down, 1 to go).
Everyone thought I was nuts, but actually it wasn't that much harder than 2 (which I've done a few times in the past).
In fact, the more things I have going on, the more organized I become.
But as my freshman year academic advisor once told me, "there's a fine line between being bored and overwhelmed".
If I were you, I would audition.
If you write out all of your conflicts on the audition form, and you should be okay.
If the director(s) can't handle it, then they don't have to cast you.
Just be careful and don't hurt yourself :)
I starred in a short film called
Magnetic Personality. Check it out!