Yes, you probably did. Ambien is pretty safe as far as overdoses: " Individuals have fully recovered from zolpidem tartrate overdoses up to 400 mg (40 times the maximum recommended dose)"
http://www.sanofi-synthelabo.us/prod...tml#OVERDOSAGE
The key to using Ambien right is to take it and go RIGHT to bed. No delay, no conversations, no phone calls, no computer. Otherwise it'll start to affect you in strange ways and you won't remember it the next morning, plus you won't feel well rested, in my experience.