yes, it's different for every person.
I've read that there is a dog that was born with a med condition and would go into frequent seizures if it wasn't for the therapeutic inhaling of the THC. *shrugs*
its impossible to say for sure but pot can effect some people in a more powerful way than others. you should be really careful because even though you cant overdose and die from pot you can get screwed up if you smoke too much or are too sensitive to it. remember its a medicine too.
It could have been laced, or you could have had a personal reaction to it ba<x>sed upon your own brain's chemistry. If you are on any kind of medications for moods, etc., you really need to be careful. Either way, be careful.