I have not had my period since november 24 2011 coupd I be pregnant?

Maybe. A physician can perform a HCG human Chorionic Gonadotropin to tell you for sure. There are other causes for periods to stop, (amenorrhea). These can include, some medications (antipsychotics, chemotherapy, antidepressants, blood pressure drugs), stress, low body weight/rigorous exercise, or hormonal imbalances. Missing three or more periods should be evaluated by your doctor.