HELP PLEASE!

Me and my boyfriend are trying for a baby but we have been on holiday for 10 days and i was due on my period while we was away so before we went i made a appointment at the doctors for a pill to put my period off until we came back home and i got given norethisterone pill 1 pill 3 times a day (dont know much about it just that it puts periods off) so i wouldn't come on, doctor said i should come on my period either the same day of my last pill as they only work for 7 hours or 2 to 3 days after well it is a week since i stopped taking the pills and i still haven't come on my period. Could i be pregnant??