could I be pregnant? HELP

Aïsha
I had protected sex and unprotected sex a few hours later the same day, he cummed on my lower back (so it was nowhere my vag) on March 24. 2 days after I had sex, I started my very first nuvaring and this Sunday I'm going to be taking it out to start my period. Ever since I started nuvaring I literally had no side effects in the first two weeks. I'm currently on my 3rd week I've been feeling nauseous, I gag but nothing is coming out. I've been getting regular discharge indicating that my period is coming soon (in 3-4 days) What's going on?