Maybe you were smoking Luwak weed.

Ever heard of Luwak coffee? On the island of Java there is a weasel-like creature called a Luwak that eats coffee beans right off the tree. The beans undergo a "fermentation" process inside the Luwak's digestive tract. The beans pass all of the way through the Luwak intact. After the Luwak craps out the coffee beans, the local villagers gather up the crapped-out beans and roast them and sell them to foreign coffee connoisseurs for $300 a pound. It sounds like a way for Javanese villagers to sell weasel crap to rich tourists for $300 per pound --- which is a really great idea!

Maybe your weed was eaten by some kind of creature --- maybe your dealer's dog ate his stash! Then maybe after the animal, whatever it was, crapped out the weed, someone picked out the nuggets, dried it out, and sold it to you. Now when you smoke it, maybe you experience the sensation of crapping which was somehow imprinted onto the weed.

Maybe you are smoking some crazy-ass shit!

I suggest getting a magnifying glass and taking a really close look at your stash. If you see anything that looks like a corn kernel stuck to any of the buds, you might want to let your buddy smoke the first bowl, wait 15 minutes or so, and see if he acts like he crapped himself. If he does, then you can decide if you want to smoke that shit or not.