Welcome to the forum, first off

Second, I think it all depends on the size of the meal vs. the size of the snake. If it's a baby feeding on 3 medium-adult sized mice, yeah too much in my opinion...but if it's a juvy feeding on small mice..maybe not so much. Do you have any pics of your snake? and maybe the sized meal he had?

Here's a chart from The Mouse Factory for comparison, in case you don't have a pic of the meal:
http://www.themousefactory.com/rates/rates.html