Suggest Medication To Postpone Periods

Hi. I'm getting married on 31st Jan. I have been having my periods regularly and based on the cycle I should have finished my cycle by 25th Jan couple of months ago when I calculated. But unfortunately, the cycle got disturbed for some reason and now I'm at risk. My new date is likely to be on 28th Jan but it is necessary that I finish my cycle by 29th Jan (29th Jan should be the 4th day). As all the rituals start from 30th Jan. As it is now too less time, I'm not clear what to do. Advancing period would be my preferred option but looking at previously answered question, I understand it is late.
My past cycle dates were 9th Dec, 14th Nov, 21st Oct, 25th Sep. Based on this, I'm due next on 3rd Jan followed by 28th Jan. Please help me with your valuable suggestions.