Why not take the mini-pill if it shrinks the growths

. Unless you give them a try followed by another scan to see if there is a result, you won't know and after all, some drugs are designed to treat problems other than what they are designed for! Were you told how long you might need to take it ?
Surely quality of Life should be uppermost in your mind, not whether a medication
might give you dementia or cause cancer

. We are lucky to have access to health care with advice. You might get a better quality of Life is you take the medication. Where did you find out that 'buscopan' might be linked? It didn't do any harm to my dog! I rarely think about what might be, if a medication eases immediate symptoms then I will have to take less in the long term. Once I feel better I stop worrying and get on.
I have slow transit. Due to being anorexic since the age of 3. It can rule my whole day

fortunately I rarely get pain with IBS. When I do I have to dash

. But oh the need to go B4 we are out and about but the bowel often doesn't play ball

Then I worry that I will need a loo when we are away from the house. Very often I am OK but it's in the back of my mind.
I would have a break of several months between bleeds, then when least expecting it, a period would arrive

. Then it would go back to cyclic. Then another gap. One has to continue with birth control until 1 has been period free for 12+ months!
You should not be taking a laxative regularly unless told to do so by a Consultant. That will make the bowel lazy ........ and can cause more problems long term than it might ease. For example, if the bowel is slow and a laxative helps but the body empties quickly: the gap between the next movement may cause a pocket of wind. Then pain relief is required and the cycle continues.
Maybe make a list of what you eat for the next 3 days and review. Also note when you eat and drink to see if there are gaps which again, may cause a build up of wind.