when am I due?

Can I get some thoughts on this? I was on the mini pill for a year after having my daughter. When I was out of refills I switched to a different pill. I started the new pill on the first day of my period in August on the 27th and bled for two full weeks among several other side effects I could no longer stand. So we made the decision to let whatever happens happen and I stopped that pack at the beginning of its third week. I remember a little more bleeding a few days after I stopped taking them but I don't know if that was considered a period? I tested some time in early October because I was feeling a little weird and got a negative but when I tested on October 14th I had a clear positive. I tried explaining this to my ob office and they couldn't say much they're just going with a lmp of 8/27 and scheduled an ultrasound. I'm just worried that the dates won't be right and we won't see much with the scan which would freak us out because we went through four miscarriages before finally having our daughter 😔