The Argentina international was delighted with his side's victory and believes that he will only get better over the course of the season.
The Serie A side shares top spot with Arsenal following this week's results, holding a three-point lead over third-placed Borussia Dortmund, and the striker is optimistic about his side's chances of reaching the knockout stages.
"This is a crucial win for us and I'm delighted. The group stage is always very complicated and we've been put in a particularly difficult group too," Higuain told the UEFA website. "All that mattered was winning and I'm delighted because these three points allow us to move joint top. We knew it wasn't going to be easy – there's no such thing as an easy game in the Champions League."
The 25-year-old, who joined the club from Real Madrid in a 42 million euro deal over the summer, netted twice to help Napoli to victory and take his tally for the season to eight goals in 13 games - but he says there is even more to come.
"I'm feeling good. I can still improve, but I'm feeling good and this is important."
Napoli resumes domestic action on Sunday when the club takes on reigning Serie A champion Juventus.