Your reaction might have been from the Tylenol, as you suggest. But I'm sure there isn't a woman on this forum who wouldn't say that having it out was the right thing to do anyway. And I know you did have it out that same day, as I recall. I would give anything to go back in time and never have it put in at all. It wasn't worth a couple years of easy BC and no periods.
I would go far enough to say that any woman with the IUD is taking a gamble. She might be fine for now, but if a season of stress or illness hits her, it could be enough to destroy her physical "balance" and cause her to start reacting.