My first pregnancy

So I'm having a hard time trying to figure out exactly how far along I am. I have a period tracker and I don't know if my boyfriend forgot to put one of my dates in. But I went on there today because from when I took a pregnancy test I'm 13 weeks that I know of. But it says that I haven't had my period since April, I haven't had a doctor's appointment yet because I've been struggling without having medical insurance. I just got the paperwork done yesterday to go see a doctor and to see if the baby is healthy. But in your guys opinion, guess how many weeks I am, because I have no idea.