Will The Period Cycle Start As Per New Due Date After Taking Regesterone Once?

I usually have regular periods with no problem at all. However, for some reason, I had to delay my periods this month for at least 12-15 days, so I used Regestrone 5mg tablets (from 5th to 19th april). As expected, periods started within 3 days of last dose (on 22nd april), though the flow was lighter than usual. I have a trip coming up next month (may) and wanted to know if the dose I administered delay my successive cycles as well, i.e., will the next cycle start according to the new date (22nd) or my previous date (8th) ?