I was on the birth control shot for three months and had a period a week before my next shot was due and I missed my shot and have not had another period sense June 20 2010 could I be pregnant or is it from the birth control

Most likely it is from the injection, some women find it takes quite some time before their cycles become regular again, but certainly pregnancy would be a consideration. Have you tried a pregnancy test? If negative, and still no period for September, might want to check with your doctor.

Yes I tried a test about a month ago it was negative... thanks