Had sex around ovulation with a condom and it came off, he put it back on(i know we should have used a new one) took plan b 6 hours later, protected?

Probably: If you took Plan B 6 hrs. later, you should be OK. Be more careful in the future.

Likely "yes": you should be protected. There is no such thing as 100% as even with perfect use all contraceptive methods can fail, but your chance of pregnancy sound very low. Next time (as you said above) - stop, put on a new condom, and continue if you want more peace of mind. Good wishes.