Need amortization help

I could use some smarter minds than mine on this matter as I am having trouble conceptualizing something.

If a borrower pays payment #1, they are at payment #2 on the amortization schedule.

If a borrower pays payment #1 plus the scheduled principle amount of payment #2, does that mean he is now at payment #3 on the amortization schedule?

Thanks.

Rolf

Wheat Hill