Period Late

I had intercourse on the 10th of January with my ex boyfriend. My period was supposed to come on the 23rd of January. I started falling for someone else I'm scared I may be pregnant by my ex boyfriend and I haven't told the boy that I'm falling for my period didn't come on for January. Anyways,  It's now Feb. 3rd and I still haven't got my period. Also, I haven't took a test yet to find out.