I have yet not went to a doctor because I just received insurance. Although I went to the health department. They asked when my last period was and based my due date off of that. The only problem is I forgot to mention that my last period started 21 in April and ended 27th in April but by the 18th in May, my period never came so I tested to make sure it was not missed because of pregnancy, which came out negative. On the 27th of May, that was actually the first time we did have sex unprotected and trying to get pregnant after conversing of the idea for awhile. Considering the last period in April was what they based it by and is incorrect, how should i know how far along I am until I get into a doctor?