Late period

I had unprotected sex 4/5 weeks ago now. I took the morning after pill within 9hrs after it happening so I thought that would be a lot better and make it work better with it being a short window frame. I had my period after that and it arrived on time and was completely normal (I'm now worrying that it wasn't a period.) I've had really sore stomach pain for weeks and weeks now, feeling sick and tired but there could be lots of reasons for that. I've taken 3 pregnancy tests and they all say negative. I'm 7 days late with my period this time round and I'm freaking out that I'm pregnant. I'm not in my home town to go to the Doctor to get them to test if I'm pregnant or not. Has this happened to anyone else? What's everyone's opinions on why this is happening to me?