No one knows your body better than you do so I'm sure you will do the right thing. Just be careful with the dexedrine. It can be habit-forming. You don't want that, for sure!
I walk my dog when I go for my walks. We walk about a mile in the morning before breakfast and sometimes walk another mile in the afternoon. She will be 13 in a couple of weeks and is in fantastic health since I started taking her with me. Before we started the walks, she was a little overweight and somewhat lazy. If I tried playing with her, she would be panting really hard with just a tiny bit of running. I just figured she was getting older....NOT!!! When we started walking, she lost a pound of weight. (She's a toy breed so she wasn't really heavy.) Then, her energy returned! Honestly! Now she runs like the wind without tiring and has the energy that she had when she was three years old! She's like a puppy again.
So, there really is something to exercising giving you energy. And, as a bonus, it helps with the pain. I do think you will notice the difference.