You should definitely see a doctor, they will do a blood test to determine if she is pregnant. It is possible to be pregnant and still have your period, many women don't know they are pregnant for several months. Be safe, see a doctor!
My wife had a positive pregnancy result twice 10 days after her period was due. On the following day, she got her period, but when we checked again, the pregnancy test was still positive. We are now confused. Is she pregnant or shall we see a doctor?
Just go see a doctor. Nobody in a forum can answer such questions unless he/she has a medical license...