The side from the capital eventually won with an own goal from Timothee Kolodziejczak, and Puel said that he was disappointed that Nice could not take advantage of an under-par PSG.
"We had some chances in the first half," Puel told Ligue1.com.
"Perhaps with a bit more accuracy we could have been more dangerous. There was a desire to recover possession and destabilise the opposition.
"Conversely, the start of the second half was disappointing. We missed some physicality in the heart of the game. PSG had a good game but I regret that we did not do more because we had the chances to. There is room for improvement."
Nice are currently 11th in the table, while PSG are 13 points clear at the top.