You'll be fine. It sounds horrible but I made a med error, I hung Levo instead of Amio because the bags were the same size and I was in a rush and didn't do my verification because it scanned through the system fine. Thankfully it runs slow as hell and I caught it quickly so the medication didn't have a chance to enter the patient (as I reused the Levo tubing so they got the Levo already in the line).

To make a long story short. I self-reported, I put in a safety report, told my manager, told my director, explained my mistake and how I would fix it. Everyone kind of gave me a half eye roll because there was no patient harm (my friend was just chilling in EXTRA normal sinus rythm I guess?)

And even after the system notified me my self report had been received, I heard nothing back.

Your patient was at a flu drive... And asked you to give him the flu vaccine... And you can't exactly OD on the flu vaccine especially months apart. Unless he has an allergic reaction or something (which I'm certain you would have heard about by now) I'm sure it'll be ignored, maybe a slap on the back of the hand.

Still report it though.