Welcome Lilith!
How long have you been on it and how much did the doc prescribe? It doesn't work right away and it may take time for your doc to get you up to the pain relieving amount. It may take up to a month for it to get into your system properly as well. That is the way SNRIs work as it is with any antidepressant. You only have been on it for a short time, give it time. I was on Cymbalta back when it first came on the market and it didn't work for me.
As you said you are new....unfortunately you will find that there aren't any quick fixes with FM or CFS. But we are here to help as much as we can.
Again welcome!