Take a look of this.
www.deviantart.com/bonnerscar/…

 

Oh goodness I have just read through your profile and saw you have fibromyalgia too! well, what can I say? I absolutely can relate, Ami! same here--I went undiagnosed for long years *since my teens--while I`m already 37 yrs old at current-- during which I was consistently accused of being "weak" "lazy" and "whiny" whenever I would find any difficulty into doing certain physical tasks or would feel pain while doing them (lifting weight, doing any physically demanding exercise and so forth were something I kept doing, but it was physically strenuous and painful for me, and even if I would carry on and not complain, my physical exhaustion and pain were evident, so I´d be just deemed "lazy" or "whiny", "too young to say I felt tired and achy like an old lady" ---)
...it wasn´t until last year´s end  that a doctor mentioned fibromyalgia to me and told me he suspected that was what I had. Later, they performed the scarce tests which would allow them to diagnose it via discarding other illnesses (such as rheuma, arthritis and so forth) ran a psichiatric aptitude test on me +to make sure I was not psycho-somatising* and finally went for an electroencephalogram. 
The readings indicated the pain I feel is real and physical, and originates in a "short circuit" on my central nervous systrem (to put it simply)--so-- I can absolutely, completely relate! it sometimes can be extremely challenging +especially given how it entails more than just constant random  pain and also comes with feats as memory loss, exhaustion, mental fatigue and so forth  
I truly understand you, and wished to let you know you´re not alone at it  
Please take care, stay strong, and keep loving art! it´s a fine and worthy motor to keep going even through this challenge!