Replying to Bad Weed?

So today was the first time ive smoked in like 3 months. i only take 2 hits because were goin to a friends house who doesnt smoke. im standing in his kitchen, when my whole head starts to ring. the last thing i remeber thinkin was wow i need to go to sleep. and than bam, i guess i was passed out for a good two minutes, friends almost called 911, the whole nine yards. my question is, has anyone had anything like this happen to them. was it the weed, or something else. oh, and im fine now, just a little headache, its as if it never happened as of right now.