Confused on how far along I am

Katy

So I got a BFP on Tuesday, and I may have wrongly assumed that the beginning of my last cycle was in early September. I had two days of bleeding in early October, which I thought must have been implantation bleeding, but based on my hcg levels, the nurse told me that the two days of bleeding in October was probably a period. I’ve never had short periods (usually 9 or 10 days) so I really didn’t think that was an actual period but maybe.

So meanwhile, I thought I was 6 weeks pregnant and turns out I’m probably only 3 weeks, which seems early to get a BFP.

Anyone been in a similar situation?