Birth control - late period 

Hi everyone, I have been on birth control for 3 months now and the last 2 months I have gotten my period on the 2nd day of the 7 day break. This month it is the 3rd day of the break and still no period. I’m very worried as I do have unprotected sex but I haven’t missed a day of the pill this month and was only late of taking one 2 hours at most and I didn’t have sex after that day I was late. I don’t really see how I could be pregnant but I know there is a chance but I was just wondering would any of you’s have an explaination for this or think I’ll get it before the last day of the break? Thank you’s