The fly-half missed two penalties and a conversion following Craig Gilroy's try during the low-scoring match.
The Ireland coach told BBC Sport: "It is too easy to put it down to the place kicking. We created a lot of try-scoring opportunities.
"I thought the rest of Paddy's game was good and strong for us. Paddy had a big influence in the line breaks, that is why we picked him. We knew he would bring that to our game.
"We have to learn how to win out these tight matches because it was six points against England and four here. We can knock on the door in these matches, but we have to learn how to finish them off."
The result leaves Ireland fourth in the championship table.