constipation with lymphatic colitis

I was diagnosed with lymphatic colitis three weeks ago. I am taking entocort, probiotics and following a gluten free diet. I asked my doctors nurse to recommend something for energy as I work in a very physical job and have lost almost twenty pounds. She recommended protein shakes. Two days later I cannot have a BM bigger than a grape and feel completely constipated and my gut hurts like it did before my diagnosis. Any ? I felt I was making progress, but dont know what to do. BTW, still waiting on third bloodwork to see if I have Celiac. Keep coming back inconclusive. Any advice much appreciated.