This could be an opportunity for you guys to become better friends or something.

You could be like "Well, I bought some, but I inhaled the fumes from the paper that it was in, and spilled the rest, and inhaled molten plastic fumes."

If he doesn't care that you smoked, he'll probably be like "LOL. get some, and I'll show you how to do it right" and for all you know, you guys could end up smoking, and you'll actually get high. Maybe he can teach you how to roll a joint.
Peace,
horror business :rasta: