Could i be prego again?

On the 7th or 8th (most likely the 8th cause it was a tuesday and i was off) of october me and my boyfriend had sex and we were using protection. he went to slide the condom on and i told him to wait and let me preform oral sex on him. after i finished i told him to go ahead and put on the condom. In the middle of sex the condom slipped off and there was already cum from the first round in it. Ofcourse i was scared and already felt as though we "fucked up" we aren't ready for our second child together. My period is 6days late maybe 5 but, a normal period for me is 5days length and sometimes 6. I already have a 1yr old (18mnths) and he has a 3yr old... could i be pregnant again. I've noticed extreme emotion for the past 2-3 days... crying or wanting to cry over little stuff. my breast haven't felt normal for 2 weeks. Could i be pregnant?