The poop thing is important. I would go back to what was working for that.
If you get enough oily fish (salmon, sardines, etc.), you really don't need fish oil supplements. In addition, some people think that it's too easy for the fish oil in supplements to go rancid.
We often know best what makes us feel good. If a doctor or other health practitioner makes a recommendation that makes you feel worse than you did before, in general, they've made a mistake. (There might be exceptions to this, but telling you to eat a meal that results in you having irregular bowel movements probably isn't one of the exceptions.)
"Right is right, even if no one is doing it; wrong is wrong, even if everyone is doing it." - St. Augustine