g-star: I bottled this up almost 3 weeks ago, has a nice hiss and some carb, but a faint head that fades quick. I figure with a big beer you need at least 3 weeks, maybe even 6 until it gets fully carbed. I did a Rocheftort8 clone that didn't have what I considered good carbonation and a good head until 6-8 weeks after bottling. This was without adding fresh yeast, however. I figure carbing would be faster with yeast that is not as stressed.
So give it a few more weeks. Besides, I figure it needs a few months in the bottles to fully condition, as most Belgian ales do. The fruit tones start coming from the back to the front, and as really interesting how the flavors develop.