Yes, Its is possible for a pregnancy to go that long. Modern Western medicine has become very diluted concerning what is healthy and normal for a pregnancy, birth, and gestation period. Doctors often push their advice onto women for reasons concerning pathology vs hollistic training, insurance payouts, time constraints, and just poorly researched information. The US seems to be the country leading in this absurd practice. Surgery and drugs should not be the solution to everything. And there is no "normal" pregnancy standard. Midwives are far more trained and informed about this. Western medicine has actually proven to increase the risk of prenatal, birthing, and early child developmental problems with there drug and fear based approach. Every other country has lower still birth and after birth complication rates to mum and baby. Countries that take more of an all natural approach, only intervening when there is a medical reason, are far more successful in producing healthy pregnancies, deliveries, and babies. I have known women whom have carried there babies well past 44 weeks (very common in Europe), and some farther. After all, the due date given to you is not 100% accurate, it is an estimate! After all, all they are going off of is the last menstrual cycle, and some women dont menstruate regularly. Even if they do menstruate regularly, they cannot predict when ovulation occurred, or when conception occurred. Its time women take back their voice, do some research, and stop being bullied by "what the doctor says". All pregnancies and women are different. I have had a baby at 46 weeks, and another come at 37 weeks. Both healthy babies, just different. I've had friends who were induced because they were told "baby was taking too long",even though the placenta showed no signs of breaking down, and both women either lost there babies to complications or had unnecessarily difficult births and after care issues for the mom and baby. Such a shame. Playing God is never a good idea in my opinion. Doctors will spout all kinds of "facts" at the mom, often making her feel pressured, instead of informed. But has anyone ever really researched these facts? I think the truth would surprise most people. Amish and mormon women are more successful at having babies in the US, and they never have any intervention from doctors. Not that I'm recommending that extreme of an approach, but, if a women is getting regular prenatal care, and there is no sign of anything wrong with the baby, the placenta, or the mom, there is no reason a baby can't go past 42 weeks. Everyone and every baby is different. It takes longer to bake a pie than a cupcake, and thank goodness we are not all cupcakes :), how boring would that get? …
SO…YES, its possible the baby is yours.