First up for Ireland is a potentially tricky trip to Andorra on Friday, before a home game against Armenia on Tuesday.
And the 20-year-old is aiming to take the frustrations of Wigan's current predicament out on both nations.
"I'm happy to be going away with Ireland, and we'll be looking for six points from those games," McCarthy told the Wigan Evening Post.
"Of course I'll be concentrating on Ireland while I'm away, because we've got a couple of massive games coming up.
"But the Wigan situation's always in your head, you're playing it over and over, asking whether I could be doing anything different. The only way I can put it right, we can put it right, is on the pitch, and it's up to us to do that."