My period is late, pregnant?

Me and my boyfriend were fooling around and at one point he wiped dripping "precum" off of his penis (it was a good amount too, probably the size of a quarter in your palm) and wiped it on his pants pretty viciously, and then rubbed my leg for about 3 minutes (so his fingers were probably dry) and then fingered me for maybe 30 seconds total because his phone rang and he had to go.

Its been a month since my last period so it should be coming any day now, but the day after that I woke up with my normal cramps on both sides. COULD I BE PREGNANT????

Its been 3 days since, im not nauseous (I had a big spaghetti dinner 2 days after), my breasts don't feel any different, I don't have any cravings, and Im not tired because I swam with my brother for the rest of the evening and we were laughing etc. Im absolutely terrified, its been about 3 days since the event, and 2 days of cramps, and still no bleeding!! I know its right around my period time so that could be what the cramps are but still!!!

Please help me :(