Stimson told BBC Radio Kent: "I got an anonymous call just after midnight, and I took my frustration out on them.
"By the time I got up in the morning, I was looking forward to the challenge of the next game, so it didn't upset me."
The Gillingham manager says it's not the first time either he or chairman Paul Scally had got anonymous abusive calls.
"Unfortunately, there are ways of getting our numbers, the frustrating thing is the callers never leave their names," he said.
"They know me and where I work but they wouldn't give me their name. That's all I ask, then we can chat and talk about the situation in another way."
The 1-0 defeat against Tranmere means Gills have not won for nine games, and saw the club sink into the bottom four.
Source: BBC Sport
Source: BBC Sport