A really good visit to my physiotherapist today. I got a lot of questions answered and as usual a lot of understanding and feedback.
He told me that exercising triggers the bodys' own pain 'medication', so on Monday I've told him I'm going to the gym at work. I feel I have a little bit of energy to do so, and I know that working out makes me feel better. And, if my arm, back and feet can benefit from the 'medication' triggered by exercise, I'm all for it! 
My physio made this drawing so I would understand what he was talking about.