My period is late by 7 days. Now normally my period is unregular by maybe 3 days not a whole week! The last time me and my so had sex was the beginning of the month of July. But it was only a in and out thing more like a tease I'd say nothing stayed in longer than a minute and I know for a fact he didn't cum inside Bc it was to early for him to. We have been together 3 years so I kinda know when he is about to nut and when he isn't even close. Anyways I have taken 2 pregnancy test both say negative. So why is my period so late?! I know stress could be a factor but I don't feel like I have been very stressed out lately. Please help