Still no period but negative tests!

I had sex the 24th of June twice and June 27th once.. The highest fertile day was the 27th but still had 8% chance on the 24th the 27th was 22%. I was due for my period between the 9th through the 13th; which that is today and I have till yet to have my period! I have been taking tests since the 5th up to 11th.. All negatives.. None have a faital line either.. They all had a evap line after 10 mins which I thought was a positive.. I don't understand... Am I pregnant or what? Today I have been having mild pains in my pelvic sorta.. I will cramp like my period is about to start for like 10 minutes then it will go away.. That happened twice.. Help?? What to do now?