Sex 5 months ago, Regular periods, 2 Days late this month! Help!

I had sex five months ago on April 3rd, I had an incident in which I thought I was preggers, I went through 10 hpt and all were negative. I haven't had sex since then. I ended up recieving normal periods until last month on July 9th I recieved my period much earlier then usual. It went on as a normal 5 day period. Now this month, I was scheduled for a period on August 8th, but it has yet to come and today is now August 10th. Could I still be pregnant? Or am I just having an irregular period this month? I'm worried because I've always been regular and never missed a period!