Stouts take 3 weeks at 40F to carb up for me. The lower the pressure, the longer it seems to take to hit the CO2 volumes you want. My stouts only see 8psi, so at 2 weeks they are definitely not ready. 2 weeks for beers that get 12psi+ seems to be enough though. YMMV.
In the future, you can put it on 2-4psi higher for the first week, then drop to your desired pressure for the next week. It should carb up faster that way. If you carb on the liquid side, make sure to switch to the gas side when you reduce the pressure or you'll wind up with beer in your gas lines.