I had unprotected sex with my boyfriend the day after my period and he came in me while I on was on top, but I'm on NuvaRing. So, what are my chances of becoming pregnant?

Since you are using birth control, it would be considered protected sex. Pregnancy is possible even with any birth control, but by using the NuvaRing you have reduced the likelihood. Sex the day after your period ended reduces the odds as well, unless you happen to ovulate on the early side. If you want to reduce the chances even more, have your partner use a condom as well.

Agreed, while always possible, you have greatly lessened the odds.