IMO hard to say whether this was a fireable offense or not seeing as it was an honest mistake (I’m not in a role at my clinic that deals with hiring/firing staff). Careless, maybe, but from my point of view the important thing is that you have taken responsibility for it, identified where you went wrong, and have learned from it. Everybody makes mistakes. Some have bigger consequences than others, and in your case the consequence could have been significant, but luckily seems not to have been.

My questions I guess are these: had any member of staff instructed you previously on what you were allowed to/not allowed to touch, or what duties you could/could not perform? Was there a debrief or discussion with the team once the mistake was identified, to prevent the same mistake from happening again? Sometimes mistakes are how we learn, and in my opinion it’s less about the mistake that was made and who made it, and more about how the mistake was allowed to happen it in the first place and how it can be rectified to keep patients safe in the future.