Gross...a black tongue!!!

The other day I woke up and went to brush my teeth and noticed that my tongue was black! UGH!!! What crazy disease do I have???? Am I dying??? These are the first thoughts that popped into my head, so I call the Dr. and talk to a nurse and she's kinda freaking out too and then she tells me to wait here comes the Dr to talk to me. He asks if I've taken any Pepto Bismol in the past 24 hrs and I said yes and that explained it all. I NEVER knew that pepto could turn your tongue black but it sure did scare me. I used my tongue scraper and brushed my teeth like normal and it was all gone and I haven't seen a trace of it since then. Kinda freaky huh! Anything crazy like that every happen to you?? I didn't take a photo of it because it looks disgusting but it you just want to see it then google it and check it out...blah!