Hi there, how much and how long have you been on subs? did you taper down or jump off. It all depends on those answers. Usually it's the 3rd day you start to feel like crap, but if you were down to a low dose, .5mg you'll still feel it. everyone is different. get some immodium and drink lots of fluids and walk or do some type of exercise.
Good luck and keep posting so others can help too, especially after you answer above questions.