There's a possibility that the iron supplement is causing you stomach pain. My gastro, who's a subspecialist in IBD, is very wary of oral iron supplements; told me yrs back that it tends to "clump" in the digestive tract. You might be better off taking Forvia vitamin/mineral tablets, which are specifically formulated for IBD patients. Red_34 has reported good things about
it in other threads here. I know that flaring UCers also need folic acid supplements, which Forvia contains. Don't be surprised by your low energy level; many of us have to fight that even in remission! Try to get as much rest as possible because it helps the inflamed tissues to heal. I myself have done better on Colazal than any of the older oral 5-ASAs so I wish you good luck with it. It can take a couple months of full-dosing to feel good results. / Old Hat (nearly 30 yrs with left-sided UC; currently on 3 Colazal daily; seem to be back in remission after July flare)