Unsure of next steps

Heres the most condensed story: I had a patient a couple nights ago that is an anticipated death and a DNR. I am still in orientation with a preceptor. Patient was ordered PRN anti anxiety and pain medication frequently to ease her passing. I took the medication from the pixus system and my preceptor witnessed the waste. My preceptor accidentally threw the vial away, apologized and said she would chart that the bar-code is unavailable when we got back to the room. We go back to the room and I see the medicine on the mar (which for some reason makes me think that my preceptor entered it, but its basically an alert saying the med has been scanned at the pixus) scan the patient and ask family the name then administer the narcotic.

I literally woke up in the middle of the night realizing that unless she did go back and chart that it was given, I didn't chart that I gave the PRN narcotic.This was 30 minutes before shift change so I did tell the oncoming nurse I was giving the med and told them again during report that I gave it and the time I gave it.

my question is what is my next step. I do work tomorrow. Do I chart the time I gave the med, tell my supervisor? Im not sure. I am hoping that my preceptor did chart that it was given but I am preparing for the fact she probably did not.

Thank you!