HIT - the wall

I finished treatment a about 4 years ago, coming up to my 4 1/2 yr post diagnosis, not doing to badly apart from my feet and tiredness.  This weekend I fought against having an afternoon nap when I hit the wall, I went for a short walk (just 10 mins), I tried to do some sewing (that ended up in the bin, stuffed it totally) and by 8.30pm I gave in...and couldn't sleep.  Tossed and turned and finally got to sleep.  Woke a couple of times through night and dragged myself out of bed at 8am.  Woke lethargic, achy, boobs sore, arm sore, back sore, legs sore, throat sore, bloody itchy.  Great I am coming down with something.  Let myself have an avo nap (21/2 hrs ?nap?)  Woke much better, and am fine today.  Slept well last night.  Oh boy.    Go back down to GP and get bloodwork done - iron, thyroid, diabetes, etc etc - AGAIN.  No nothing wrong.  So what do you do, just accept it.  Laugh when you have friends over and I have to have a nana nap...yeah have to laugh or I'd cry.