AM I FERTILE

My partner and I just had unprotected sex today and went straight for it. Now I'm suppose to have been on my period, I come on every third week, even though I've been stressing lately so my periods don't have a set schedule anymore. So my question is, am I still possibly ovulating? When should I or should I bye a pregnancy test? And lastly, even though my bf let his "friends" loose today, and I come on my period 2moro could I still might be pregnant?