Why The Menstrual Periods Are Delaying?

So my period is late and May is almost over! I havent had sex since like December... But January February march and April I have had regular periods... could I be pregnant!?? Or am I just freaking out...I do play soccer..and some ppl r telling me that it may be the reason...but I only play 2 times a week. If my job isn't on the way...