Hi Karen,
I too have fibromyalgia.  However, mornings are best.  Pain sets in with low weather pressure fronts, when it cools down and evenings.  The key is it is an inflamation disorder and the two herbs that help the most is tumeric (which is 10 times more effective if taken with green tea) and cayanne pepper which we use with fresh squeez lemon juice and maple syrup.
I did go the guaifenesin route but like the above better.  Good luck with this. 
