Could I be pregnant(long post)

Okay so on may 21st my bf and I had unprotected sex. We talked about having kids but weren't necessarily trying.

So last Tuesday morning I fell in the shower wasn't scheduled to start period until the next day. So when I went to urgent care they ran a pregnancy test and it came back negative the nurse said we could have taken it too soon. So the next I started what I thought was my period but I only bled for a day (normal is 4-5 days). So I waited a couple of days and took another test it was also negative. Now ever since then my body has been acting weird, I have been more tired than normal, my sex drive is up more than normal, I have been more moody than normal, I didn't have a normal period for this month, I have had slight cramping and bloating that I usually get for 1 or 2 days with my normal period and it's been more frequent. And I present alot of the symptoms of a pregnancy so this morning I took another test and it came back negative again. So if I'm not pregnant than what else would explain these symptoms?