I NEED answers please don't ignore

My last period was May 9-16. I had sex on April 18. We used a condom and the boy did not cum in the condom or outside it he didn't cum at all. I skipped my period and am seriously freaking out that I could be pregnant. I'm 5'9" and only weight 120, I lost 10 pounds a few weeks ago and was extremely stressed out due to school. I have a history of irregular periods but they've been regular lately. Please someone help. Should I take a pregnancy test or am I just being ridiculous?