Talk to Gynecologist on Extended Periods/Menstruation

My wife is 30 years old and mother of 3 kids with youngest born 2 years ago. She had recently stopped breastfeeding the youngest child.

She had her regular periods from 15 August to 21 August. Then on 24 August she had to take ECP tablets (Levonorgestrel), we made no contact after that.

Then surprisingly she had her periods on 30 August a week after having the tablets on 24 August! That'd be 2 weeks before she was due again on 12 September.

She has her regular periods for 7 days but this one started on 30 August and continues till date, 12 days have passed now. Apart from the duration, the blood flow seems normal and there are no other issues.

This is very unusual, how concerned should she be? Any medication she needs to take to restore the normal periods? Anything else she should take care of.