Yes, you need to wait longer. The damsels may complicate your cycle, if your local fish store will take them back you can cycle a bit faster with no fish.
If you had no fish, you could put a large ammonia source like a dead shrimp or overfeed it with fish food to speed up the cycle. If you never see an ammonia spike while the shrimp/food gets all consumed by bacteria, then you've had a silent cycle.
The quality of the live rock and the care it got in transit can vastly affect your cycle time. Anything from an extra long cycle because of a large amount of dying stuff on the rock, to an extra short cycle because it has a ton of friendly bacteria and nothing dies on it.
I'd wait at least 6 weeks before calling it a silent cycle. 10 days with no ammonia could just be that the bacteria that break down fish food into raw ammonia have not built up yet.