Is there any way I could be pregnant?

I'm sorry if this question is dumb! I genuinely don't know and I'm a bit paranoid! I had sex on Feb 4th and had my period on time on Feb 16th, although the first few days were unusual (it was extremely light). I have not had sex ever since but my period is late now. I've never really been late before-always exactly on time! Since I have technically had one period since...I don't know? Is there any reason to worry?