Pregnancy Dates More Condition_symptoms What Is The Actual Determination Of Pregnancy And Due Dates?

What is the actual determination of pregnancy and due dates? - pregnancy dates more condition_symptoms

I am 19 weeks pregnant! But I slept with this kind since 26 June! First day of the menstrual cycle, last June 12! This would mean that I was pregnant before I met him, but that's impossible! She had a miscarriage 7th May due to an incident! They have something to do with it? I do not understand! Please help me!