Stokes sorry for frustration over dropped catches in England loss
The visitors were left to rue two dropped catches on day three in Multan, Salman Agha escaping on four and six on his way to a crucial half-century as Pakistan made 221 in their second innings.
England were left to chase an unlikely 297 to seal the series with a match to go but never got close on a sharply turning Multan pitch that was recycled from the first Test.
It was Pakistan's first Test win at home since February 2021.
"No one means to drop catches but it just proves how important catches are out in these subcontinent conditions because they don't come along that often," skipper Stokes told Sky Sports.
"I actually apologised to the group up there last night."
Stokes, who missed England's innings victory in the first Test in Multan because of injury, added: "It's the first time in my captaincy that I've let my emotions, how I was feeling as the game was unfolding, show in my body language.
"I owned up to that and I'm very annoyed with myself for letting that out and it's something I don't want to do or be seen to be doing.
"So I apologised to the group about that and I said it was poor old me coming out, tired, grumpy old man last night but you won't see that happen again."
The third and final Test is in Rawalpindi from October 24 and Stokes refused to look backwards or wonder what might have been.
"Next week is going to be good. I'm sure everyone's enjoyed watching here and back home," said the skipper.
"Hopefully we can get a win next week and go home with another series win."
England swept a three-Test series in Pakistan in 2022.