@Newbootstoday Keep it simple. I think you are a little bit confused on how to use it but that is not your fault - you've not been given the right advice.
During peri, you can't follow your own cycle. That's because it will become irregular- as it has now.
You have to use HRT to set a new 'HRT cycle'.
So, rather than using your own cycle for the 12 days of Utrogestan, you have to use a date on the calendar.
The way to do this is to choose the same day each month.
My consultant suggests women use the 1st of each month ( Day 1 for Utrogestan and keep to that for 12 days) or any day as long as you keep to it.
If you wanted to, you could allow your bleed to finish - it is probably your own period- not a withdrawal bleed- and start Utrogestan on 1st Jan.
OR you can take it today for 12 days, and then again on 17th Jan.
If you start it today, you may get a slight withdrawal bleed in around 14 days' time (2 days after the last Utrogestan.)
@CelesteM You don't keep bleeding when stopping Utrogestan- when the lining is shed, it's shed, until the next withdrawal bleed (or a normal period.)