The game was decided in the space of eight minutes when midfielder Jay O'Shea opened the scoring before Marc Richards bagged two goals to give the Spireites their first win of 2013.
Boothroyd admitted: "When you go on a little run and people start to talk about you, you have an opportunity to build a reputation and that reputation can sometimes be better than you actually are.
"I am thoroughly disappointed because we never played for 30 minutes and you can't do that against teams that are up for it. You have to give credit to the opposition but we were complacent and thought we were better than we were for 30 minutes.
"We got a good hiding and when you get a good hiding, you have to take it. We have to make sure we learn lessons from this. We've still got a lot of work to do and that first 30 minutes was unacceptable in so many ways."