McCarthy has been unable to guide the Tractor Boys away from the Championship's relegation zone since arriving at Portman Road.
He said: "We are brittle and timid at the minute and if you want to describe it as awful and abject I am quite happy with that to be fair.
"We talk about being hard to beat and not doing anything stupid and then we give away a penalty. The manner in which we conceded the goals today was dreadful. It was embarrassing to be honest.
"It hurts me as a manager because I take pride in my teams being organised, tough, resolute and hard to beat.
"There is no point arguing about whether it was a penalty or not. If we had gone across and cleared the ball there would be no penalty.
"This was awful. There were no positives and we have to try and make sure it doesn't happen again."