Confused on how far along I am

Alyssa

I had my first appointment a few weeks ago and at that time according to my period I was 9 weeks 4 days.

The baby was measuring at 8 weeks 6 days.

When you are counting the days, do you count the 7th day and part of the same week or does that start a new week? Does that makes sense?

Is it 8 weeks 7 days or does it move to the 9th week?

Not sure why this confuses me so much 🤣