When I did a cold extraction of codeine because I was out of my codeine-containing medicine for my migraines. It was supposed to take out the tylenol and leave me with shitty tasting, but migraine-diminishing codeine.

It worked. But the next morning I woke up feeling really strange. So I thought I was dying from accidental tylenol overdose. I was rushed to the hospital, where they tested my blood, didn't find significant amounts of tylenol, but very significant levels of morphine.

My "feeling weird" was a "morphine high". Needless to say, I am not going to get addicted to that crap any time soon. But yeah it was scary, thinking I was about to die. At least now I know my cold extraction technique is on point.