Okay, so I had two 500 mL "bottles" (that's pretty tiny) of this in the space of about 10 minutes, my first time drinking. Is it surprising that I don't feel hungover at all? I know next to nothing about alcohol, other than this was 56 proof, so that's 28% actual alcohol.
EDIT: Oh, in case anyone's curious what I drank was so old that it used the original name, "Amaretto di Saronno," rather than the current name of "Disaronno Originale."
Not necessarily. Some people just don't get hangovers (I don't think I've ever had one despite having been shitface drunk entirely too many times before). Plus it sounds like you didn't continue drinking and weren't actually drunk so that's probably another factor.