Sharp was given a rough ride by Scunthorpe supporters despite the fact he netted 56 goals in just two seasons for the Iron before moving to Sheffield United.
The 23-year-old whipped off his shirt and ran over to the Rovers fans after putting his side 2-0 up on Saturday but revealed he had not planned to celebrate scoring.
Sharp told Scunthorpe's official website: "It was my first goal for Donny. I didn't want to celebrate but I was getting some stick from the fans.
"I don't mind that but I didn't think I deserved it and I was just giving some back."
He added: "I had two of my best seasons here and might not have seasons like that again but I'd like to apologise to the fans. It was just a bit of banter as they were giving me alot of stick."