my periods are 15 days late am i pregnant

I had sex 4 days after my periods and again 4 days before now I am 6 days late I have just had a baby 8 months ago can I be pregnant.

Last month I had my period just for two days although it was heavier than normall, now this month I am 3 days late on my period normal dates or 5days late counting I just got my previous period for 2 days, pergnacy test showed necitive but could I be pregnant?

I had sex on 18dec,after that I had my periods on 13 jan next on 17 feb,now my periods are 16 days late,I'm I pregnent are what I'm not understanding help,tell me details about pregnency

How much late in body pregnancy harmons could be produced for positive urine pregnancy test my periods are already 15 days late how long more should I wait for test?

Hi... I'm 25. My periods are supposed to come 15 days back but still its not. I've not had any sexual course either. What could be the reason? What should I do to get the periods back on normal? This has not happened before. Previously,I used to get the period regularly on time. Appreciate...