I recommend that you use nvm instead of "nm".
Guy: So, what do you think of my pic?
Girl: Oh wait, brb phone.
Girl: nvm, Mom got the phone.
In contrary to popular belief, "nvm" doesn't mean "nevermind" or "not very much".
Multiple government agencies have tried to hide the real definition of this three letter acronym. Urban Dictionary is now exclusively revealing it to be "naked vagina monster".
You heard it here first. nvm: naked vagina monster.
Friend: The girl I told you about, she's not what I expected...
You: You mean she's retarded?
You: SO SHE'S A NAKED VAGINA MONSTER?
NVM is the Latin letters of NUM or Numa Pomponia from which the word numismatics originates.
NVM you are good with that girl.
not very much
another word to use instead is nm which is not much
Guy-"do you like my new shoes"