Am I crazy?? Opinions please

I got a positive pregnancy test last week and it was immediately a dye stealer.

My last period started on the 1st of September but I only bleed for 2/3 days when I usually bleed for at least 7+ days which was extremely odd when I think back now as I hadn’t had a period before that for over 8 weeks, I had been stressed out about planning my sisters wedding so didn’t think anything of it at the time.

My periods are irregular and i had been sick with cold/flu twice since 1st of September hence why I didn’t immediately assume the reason I was feeling so awful was pregnancy 🤦‍♀️

I have been trying to guess how far along I am going off my last period being the one where I only bled for 2/3 days starting 1st of September meaning I could be anywhere from 6-9 weeks pregnant but now I’ve been thinking about it more- am I crazy to be thinking I could be even more than that??

What’s the likelihood that my last period wasn’t actually a period? That’s not sensible, right?

My belly has already popped but it is my third baby, also maybe just bloat? It seems a bit too firm to be just bloat tho.

I’m in the uk so it isn’t as simple as just calling for a scan, I have notified my doctor and I’ll receive my appointment letter in the post and all I can do until then I guess.