Need help trying to figure out how far along I am?

Sometime in June, I decided to stop taking my birth control to try for our first baby. I know birth control can make your body all crazy and out of order, which is why I'm a little confused as to when I actually conceived. I know I won't know the actual due date until I go to the doctor, but my first appointment isn't for another few weeks and it's been driving me crazy trying to figure it out! So after I stopped birth control in June, I got my normal AF at the beginning of July. Then, 2 weeks later, I got ANOTHER period! This period was very light and only lasted a few days but it was weird because that had never happened to me before. After that, I didn't get another period up to this day, obviously, because I found out I was pregnant. I took pregnancy tests very frequently up until August 11th and they all came out BFN.. I didn't know what was wrong with me, so I stopped taking tests. Then, when I started to get more pregnancy symptoms, I took a test on August 28th and finally received my first BFP. So, with that information said, what do y'all think? When did I conceive and how far along do y'all think I am? My guess is somewhere between 5-7 weeks, but I wanna know what others think!