Hi I'm Just Really Worried If I Might Be Pregnant.

Hi I'm just really worried if I might be pregnant. I had unprotected sex three months ago and have been having my periods regularly. Maybe a few days late or early but that's happened to me before. I also took an at home Clear Blue pregnancy test about a month ago and it came out negative. I was relieved but I still worry so much. I really need help. Thank you for your time and I hope to receive a response from you soon.