Has anyone ever had their period around it’s due time. Bfns but gone on to be pregnant?

I realize how stupid that sounds. I’ve had my period, it was 3 days late and a couple of days shorter than normal and I got bfn.

However, I finished that period 4 days ago and I’m having all the symptoms I had when I’ve been pregnant before. (Once successfully)

I know it’s probably in my mind etc but I was just curious to hear if anyone else has had similar experiences ? X thank you for your time and baby dust to all xx