Pregnant or Late Period

So, I had sex about 14 days ago, right before my period was supposed to start. I'm now 10 days late for my period and I'm not sure. The tests ive taken came back negative and all but during the day, I have no pre-period symptoms. However at night, like now, once I get into bed and all, I start having cramps like usual before my period but they're gone by morning and still no period. This has happened the past few nights.