depends, what is the gravity at? too high a gravity and the yeast will be unable to pull in any nutrients through their cell walls. This is one of the main reasons for making a starter for high gravity beers (the other main reason of course is quantity of active cells).
give it time. I doubt you killed it, but if its too thick the yeast will likely remain dormant since they can't pull in nutrients.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10