Jose Mourinho's side ensured they will finish 2014 top of the table with a 1-1 draw with Southampton on Sunday, a result that sees them stay three points clear of Manchester City – who were held 2-2 by Burnley.
Chelsea needed to show their fighting spirit at St Mary's Stadium after falling behind to a Sadio Mane goal in the 17th minute.
They earned a point thanks to Eden Hazard, but were unable to find a winner in a lacklustre second half, more notable for Cesc Fabregas' controversial booking for diving.
Terry was happy with their display despite dropping points, and he expects Chelsea will have to dig deep if they want to claim a fifth top-flight title.
"We know we're playing well but teams out there are making it tough for us," he said. "We are top of the league and everyone wants to beat us or upset us.
"It's about putting a good run together now.
"We are playing some really good football and it's important we maintain the way we're playing and the mentality we are playing with as well: a kind of quiet arrogance."
Chelsea's next test comes on New Year's Day when they travel to White Hart Lane to face seventh-placed Tottenham.
