Hey! I did the same thing two years ago, and it really seems like the meds were making no difference for me. I think regular cardio exercise is way more important. And although it seems counterintuitive, the exercise will make you less tired in the long run! Just start with something easy, something you can handle well, but do it regularly, make sure it's in your routine. Especially if you go off meds, "exercise" will be your meds, so you must practice it regularly. 35 minutes of running on a treadmill three times a week works well for me, I only don't go more because I injured my foot last year.

Anyway! Call you doctor (I hope s/he's good) and good luck!!