Am i pregnant?

So about a week after my period, i had unprotected sex about 3 times (but he pulled out) and then sex with a condom about 3 more times. I got a sample birth control from my ob/gyn (nuvaring) and was instructed to start it on the first day of my next period, which i did. My period then lasted for over two weeks, ranging from spotting to a light flow towards the end. I thought this was strange because my period is usually only 4-5 days, but i know that starting a new birth control can make your period weird. I had sex about 6 times (sometimes he ejaculated inside of me but I was protected because of the ring). The next time my period came, it lasted only 3 days, which is really weird for me. My period should be starting in a week but lately I've been peeing a lot more and feeling nauseous so I'm getting kinda freaked out. Could I be pregnant?