My boyfriend ejaculated on his stomach while I was lying down next to him with my skirt down with no underwear on. I was lying on my side so my legs were closed. After he came he did not touch me at all and we got up and he went to clean himself up. Last to last month my periods started on 21st then last month they started on 15th or 16th and I thought it was maybe because I had taken 3-4 different medicine at that time (for my migraine). Usually my periods start 3-4 days early but now it's 14th and my periods have not come. Could I be pregnant? I'm really worried. I can't let my parents know about this.