Wtf is happening?Need opinions!thanks!?

I know you guys are sick of my questions but i'm soooo confused...i had my period in July 12,then i had unprotected (pull-out method) wih my fiance between July 28-August 6.I had my period in August 13 and it was as always.After that we used condom and we checked it every time we finished.My cycle is about 35 days.Today it's September 19 and nothing.My hurts and i had period cramps for 2 days,however today i haven't any.Yesterday i took a pregnancy took and it was negative.I don't know what to believe.I'm taking another test on Monday.What do you think guys?