The Blues were knocked out at the last-16 stage of Europe's premier club competition, losing on away goals to Paris St Germain after draws in both legs.
Terry, who won the Champions League with Chelsea in 2012 but did not play in the final due to suspension, told The Sun: " I didn't sleep a wink all night - but you know it would be horrible if I did
"If I got home and went to sleep, for me something would be telling me, 'You know what? Time's up'
If you're not caring, something's gone
"But I do realise as well that there's a game three or four days later and you have to pick yourself up, you have to go again
You can't dwell on it."
Terry was also effusive in his praise of Chelsea boss Jose Mourinho, whom he believes has a ruthless streak in his drive to succeed - as evidenced by the selling of key players since returning to the club in 2013.
"He wants the best out of everyone on a daily basis," the 34-year-old added
"You look at some of the world-class players we've had - Juan Mata, David Luiz - players like that who've left the club
He's seen something - I don't know what - to let those big players go
"He makes big judgment calls and gets them right.
"He also knows when players take their foot off the gas
He can sense something before the game
He just gets a feel for everyone and every single game
And I look at that and think no-one else that I've experienced as a manager has got that."
Source : PA
Source: PA