"We didn't do things like we normally do and it wasn't our best day today," Goal.com quotes the Barcelona star as saying.
"I'm disappointed with how things played out for us tonight, but this year was very positive for our national team."
However, Messi went on to acknowledge that Argentina have been in good form in competitive matches, and admitted his happiness with his own form at present.
"[Argentina] won important matches this year and things have been great for me at club level and on a personal level too," he added.
"Every match we play is just as important as the others because when you play for Argentina, every match matters."
Argentina currently occupy the top spot in their World Cup qualifying group.