Will I Get My Normal Periods After Stopping The Norethisterone Tablets?

I am about to take norethisterone to delay a period. Once I stop taking it and my period comes, does the first day of bleeding count as the first day of a period? Or will my body realise there was a delay and revert back to my normal cycle? Meaning I will ovulate earlier in the cycle?

I am 41, 5'3", 8 stone 13