My understanding is that ectopic pregnancies do happen very early, but I think they are quite rare. What I can tell you about getting pregnant is that it doesn’t hurt, but when you are due to get your period, you get cramps that can be worse, and you think you are getting your period any second, but you don’t get it. You are pregnant. You need to distinguish between the between real pain and the stronger cramps. Check with your doctor if you are having pain. Ectopic pregnancies can be dangerous.