Also try to do some real weights, that multi gym thing is crap.
Tips for kickboxing:
1) groin guard, shin/instep pads, hand wraps all essential for sparring (and gloves of course
)
2) if you don't stretch a lot in class, stretch before
a lot, legs especially
3) be ready to be hit a few times... it might hurt a bit
4) when sparring keep hands up, keep moving
5) throw combos, most people when starting only throw individual punches properly
6) most importantly have fun