scared and new to this

Hi. So I’m new to this whole talking about my problems. I usually just talk to my friends. I know I’m probably overreacting but me and my boyfriend had sex on the 21st of December. It was the first time for the both of us. He used a condom and it didn’t last long. But my period was late by 8 days in January. I usually get my period on the 11th or 12th I am very regular but it didn’t arrive until the 22nd. Is this normal? Should I be worried? I had normal PMS symptoms prior to when it finally came. (Sore breast, headache, fatigue, nausea, cramps etc). Please help me. I am one to stress easily. So it would be appreciated