I Have A Huge Hiatial Hernia And A Gallstone I

I have a huge hiatial hernia and a gallstone I must eat small and have 6 meals a day. I have very low energy, but blood work has come out well. My iron levels are normal. I take Sucralfate 1 gm 2 times a day, also, Paxil 30 mg daily. I also take Nexium 2 times daily. My question is: What may be causing my low energy level? I drink plenty of water and I walk.