Pregnant while breastfeeding?

I have been breastfeeding my daughter for almost 11 months. I think I might be pregnant, but do not know how to distinguish the differences since my hormones are still out of wack. I've had my period since she was 8 weeks old lasting 7-11 days each time. It finally got back to normal 5-7 days for my last 3 cycles. I ovulated this month, so ttc prior and during ovulation.