Is anyone successfully taking Cymbalta for fibromyalgia pain? Anyone switched from pain meds to this?

I've been dealing with chronic pain for a few years. I've taken a lot of narcotic pain relievers during this time, and for the last year I've been taking tramadol for pain. I'm in the process of quitting and starting on Cymbalta with the help of a PM dr and my PCP. I made this decision because of Cymbalta's pain relieving claims. I'd rather take this once a day then be on the pain med roller coaster and feel like I'm being treated as a drug seeker. I'm nervous though. I'm afraid of side affects. Will it keep me up at night? When's the best time to take it? I know I should just bite the bullet and take it to see. I haven't taken tramadol in 2 days and my pain levels pretty high right now.