Could I be?

My boyfriend and I went bare for about two thrusts last week and were just like "nope we need a condom and not a baby" so he put one on. My period came the next day, two days early. I just finished about three days ago. Today I woke up a little nauseous and had a medium amount of thick spotting. Is there a chance I'm pregnant even though I had my period or am I totally psyching myself out right now? I'm totally freaking out because that's the first time we've gone bare and I really cannot have a baby right now.