Change of Shift Expiration

Well yes I am an RN and yes I have been one for a long time, but I have not done bedside nursing in many years, and had to go back to it after my great clinic job went under. So I am now a Medical/Surgical Nurse. I had no idea or could ever remember how hard this job can be. Well, anyways, since I have not been doing it long I am lucky to have not had any one die on my shift. We all know the saying "Not on my shift", well I get report that I have a "comfort care" guy who has just come to us from an outside nursing home and has been with us maybe 2 hours. I am told he is a no code and to keep him comfortable. Well, I ask the day nurse "is he going to die on me?" and she says "I don't think so". That makes me happy. Well, I believe that when a patient is there to pass they ought to be very comfy so I give out the goodies as often and as much as allowed. The day nurse says she has given him some morphine around 1 pm and he can have it every 3 hours. I must say that I did check him as my first patient and he was breathing. At 4 pm I decide it is time to give him his goodies. I go in there, say a few words and give it and say a few words and leave. I finally figured it out about an hour later that he was gone when I was talking to him, and giving him the morphine. I think he passed on a minute or so after I saw him at about 3:15. Does this make me a bad nurse?