Hi, on January 19th I had a positive pregnancy test, but the only problem is is I do not know when my due date would be. I have a daughter that was born on 10-15-15, and because I had been breastfeeding for her first 2 months, I did not, and still have not had a period so I'm unsure as to when I conceived, especially since my BF and I have a very active sex life. At times we were pulling out and other times just going with the flow. How would I determine when I will be due?