My last menstrual period was september 23, 2012 and lasted for 39 days could i be preagant?

Probably not: Anything is possible but pregnancy can easily be checked with any of the readily available home pregnancy tests. Obviously, 39 days of bleeding is not normal and you ought to be checked to try to determine why this happened and to rule out any serious problems.

Always possible: I was taught in my training and have seen in 35 years of experience that when a woman who has "pregnancy potential" comes in with unusual menses or cycle....The first thing to be checked is whether or not she is pregnant. In a large percentage of these ladies you will find they are pregnant. Dr. P.

Pregnant?: Pregnancy is always a possibility. Purchase and perform a home pregnancy test. They become positive when you are about a week late. If it is negative, repeat in one week.