The Portuguese veteran moved to the Stade Louis II from Real Madrid in the summer and has been an integral part of the team who have climbed to the top of the Ligue 1 table.
"Our first results have been positive," Carvalho told reporters. "I feel good in the team and, above all, I feel good physically. I had a good pre-season. When the body's fine, mentally things are fine too. I feel useful to the team and enjoy playing as much as ever. It's a great start and it wasn't something that was easy to envisage given all the movement in the close season.
"There's a lot of quality here with experienced players and young promising players, but that's not enough to make a team. We're still building our team and it's great to already be picking up wins and points. That's the best fuel for our confidence. What I'll retain from the opening weeks of the season is the great spirit in the squad and we're all moving forward together.
"I would have liked to have carried on because the team is going well and personally I feel very good physically. But this break is welcome after all the work put in in the last two months, generally in the extreme heat. It allows some players to recover from minor niggles."
Monaco host Lorient on Sunday.