How can i tell how far along i am?

Allenspach12

Im pretty sure we are pregnant, we have taken 4 tests and they all came up positive but im not sure how long i have been. i see girls on here posting that they know how far along they are before they go to the doctors the first time. i tried to calculate it but im just not too sure. my last period only lasted 3 days which is very abnormal for me also it was 8 days late that time and when i took the test it said negative. I am about 10 days late now with 4 positive tests under my belt and wondering if there is any easy way to know how far along i might be. i cant make an appointment yet either cuz we just got married a month ago and i dont have an insurance card yet. please help i dont know what to do!