I am amazed how many of us were super into physical activities and doing heaps in life just to be stopped dead by pmr! You are definitely not alone and someone here has mentioned keeping a diary- maybe physiotherapist suggested this also and it was incredibly helpful to me- not surprisingly I found that stress impacted my physical state more than anything else, but everyone is different, so keep a record of food, what you can and cannot do etc along with all other stuff that is happening. 15 mg is quite low - I started on 20 and my doctor seemed to think that was a low place to start!