Pregnant?? post partum?? Help!!

SO! I had my baby boy 3 months ago.

At week 6 post partum, my husband and I had sex. We didnt use a condom but he pulled out (yes I know not effective birth control...) I had what i thought was a period at week 7. It was 7 full days of heavy heavy bleeding with lots of blood clots. I've never had such a heavy period before in my life! Like used the really thick post birth pads!

We had sex again week 11 post partum. I still havent had my "period" again. Is it possible I'm pregnant again?? Has anyone experienced an early period after giving birth? Help!

PS. I am breastfeeding/pumping full time about 1100-1300 mL a day.