The sitzmarker test is done to study the function of your colon. It shows the dr if your colon is working properly and if not what part of your colon is not working properly. They can tell by where the markers are and how many are there. If there are many in one spot, that is where there may be a problem with the function of your colon.
I would ask your dr about the results of the tests and to show you where the markers were throughout your colon on the 5th day.
I hope this helps you. If you have any more questions, I'd be more than happy to help if I can.