I was really very pleased with the performance, proud of the performance," McCarthy told BBC Radio WM.
"There is a sense of relief, of course there is, because of the need for a win and for a clean sheet.
The best way of getting belief is by winning. How do you do that?
"We haven't done anything different all through the time we've not been winning.
"We were playing the same way - what I would say is we were better in possession of the ball, we passed it, we worked it."