I gave my wife amphetamines as she was trying to fall asleep after major surgery
What did you think would happen when you did that?
Well, I thought it'd help but I had no idea she would eventually have a heart attack.
Of course something bad would happen! That's why you shouldn't give people drugs, especially illegal ones, unless you're their doctor. Bad stuff like this happens when people do that!
I wasn't trying to hurt her!
But you did. You should have never given her drugs or anything else without doctor's advice first.