Save the note. Unless a Boss or Supervisor says something, leave it be. Your Co-Worker could have misunderstood something and unless they're taking it further than a note they left you, I'd let it be. But save the note, just in case she does something further.
CYA, lady. This is your job and your livelihood. If you think you'll be in trouble for something you did correctly and it will solve the issue to jump in first and submit to the supervisor, then do it. I would not be worried about starting trouble, just making sure that your ass is covered.
Give the note from the AM passer to your supervisor. Tell her to look at the history & see that the resident has has no pills to choke on.
I agree take it to a supervisor. Better safe then sorry
I would ask for a meeting with supervising staff and let them know what's going on and how it's making you feel.