I work in an ICU setting in the nights. My patient who is intubated was on a Fentanyl drip at the rate of 150 mcg, for the whole shift. Just at the end of the shift since I had to turn my patient i increased the dose to 200mcg. After I finished turning him etc.. I meant to go back to the original dose that was 150 mcg, but I was in a hurry and I accidentally put in 15mcg instead of 150. I did not realize this until i reached home and received a call from the nurse to verify the dose. The patient basically received a 15 of fentanyl for about 1 hour or so.I am new in the ICU ( less than a year) and this is the first time this has happened. I am not sure what they will do about this but the Rn seemed pretty upset about the situation. How big of an error is this? Also, we always check the drips after giving report, but the RN got busy with the other patient and said she will do later. I have learnt my lesson to be careful and not rush with medications. Any input/ advice will be highly appreciated.