What's going on?!

So I always get my period by the 3rd or 4th day of my placebo pills. It is now the 5th day and I haven't gotten it yet, Monday I had a little blood in my discharge when I wiped but it wasn't like alot it was just enough to add color to my discharge bit after that I've had nothing. I take my birth control everyday just not exactly at the same time, and my boyfriend and I have had sex a few times before I took my birth control which caused me to take it about an hour or so late. Could this mean I'm pregnant?!