Suggest Safe Alternate To Extend Periods

Hello Dr, I'm 27 yr old and getting married in 1 month 10 days...I have irregular periods right from the starting of my first menstruation cycle. I took treatments from 2-3 gynecologists earlier but it couldn't worked out well. However one of them have detected that I have few small cysts on ovaries. About a year ago my TSH level was 7.48 which is become normal now without any specific Thyroid treatment. As a part of family history, my father has a Thyroid problem. Currently my gynecologist had prescribed me 'Deviry' tabs to be taken for 5 days to induce my period since it has not occurred in last 3 months (only few days spotting occurred twice in this period of 3 months). However, I took only one tab of Deviry on 22-Oct night and my periods started on 23-Oct. Since I observed a proper bleeding as that happens in menstruation; I stopped taking Deviry further and on 23-Oct night itself (the 1st day of my period) I started the 21 days course of 'Diane 35' tablets as per her prescription. However I have noticed that I had a bleeding only on first day of my period and after that no bleeding occurred as a normal menstruation cycle...Earlier I used to have normal menstruation bleeding for 4 days. Now since I have already started Diane 35 and if I calculate the days, my next estimated periods date can be after 12-Nov. After that I will restart my Diane 35 therapy for next 21 days. And then my 2nd estimated period could occur after 10th Dec; however I want my periods to be occurred after 16-Dec. My 1st question in this scenario to you is that can I ignore my worries of having only one day bleeding occurred and continue with Diane 35 and wait for the next period or do I need to take any medication now. Also, Can I take Diane 35 pills more than 21 days (6 more days) to extend my periods for marriage reasons? Kindly help me out. Thanks!