How long have you been on cymbalta? I think generally can't they tell if it would be a side effect from a medicine in the beginning? I don't know though. Physical illness can come from depression, too, though. I'm not sure what to suggest. Maybe make sure you are eating and sleeping in healthy ways.. if you mess those two things up, they can mess up your physical health too. I hope you start feeling better and that your doctor has a good solution