[alaskayorkie]

That sounds like a small amount. You should be OK. I googled it, and the site below says it would take 2-3 candybars to truly sicken a 10-pound dog.

The symptoms of poisoning:
Within the first few hours, the evidence
includes vomiting, diarrhea or hyperactivity. As time passes and

there's increased absorption of the toxic substance, you'll see an
increase in the dog's heart rate, which can cause arrhythmia,
restlessness, hyperactivity, muscle twitching, increased
urination or excessive panting.


Here's where the info came from:
http://www.petcaretips.net/chocolate-poisoning-dog.html