As Newcastle boss Steve McClaren reflected on a "self-inflicted" defeat and 12 games remaining to climb clear of the relegation zone, Hiddink looked towards Tuesday's Champions League match with Paris St Germain and next Sunday's FA Cup clash with Manchester City.
Terry was poised to undergo a scan on Sunday after being replaced before half-time at Stamford Bridge.
Hiddink will await the results but hinted the 35-year-old would not be risked with such a short turnaround before the last-16 first leg at Parc des Princes.
Hiddink said on Sky Sports 1: "Tomorrow we'll know how serious he is. Midweek is already Tuesday and we have just two days to recover.
"I think teams need at least three days, but we don't have so we'll see what will be the outcome tomorrow."
Hiddink added in his post-match media conference: "We must calm down and take wise decisions towards Tuesday and towards the upcoming weekend."
Hiddink repeated his belief - one held by predecessor Jose Mourinho - that Premier League teams playing in Europe must have more favourable fixture scheduling.
The Dutchman said: "I'm strongly in favour, when you have to play on Tuesday, then we should play on Friday.
"I know there are commercial reasons not to do so, but sports have to be on top of that."
Chelsea play PSG for a third straight year, with Hiddink insisting the Ligue 1 leaders are favourites despite the Blues' boosted confidence from the emphatic defeat of the Magpies.
"The European game especially against PSG will be much more difficult, because it's a team unbeaten since August," Hiddink added.
"But this game gave confidence to the team. We have to go there and play with the confidence we showed today."
Diego Costa struck his eighth goal in 10 games, Pedro scored twice and Willian and Bertrand Traore were also on target, with the Magpies replying late on through Andros Townsend.
The Blues are unbeaten in 12 games, 11 of those under Hiddink, who recorded a first Premier League home win of his second spell.
Hiddink added: "We were unbeaten and we were not really proud of that. There were too many draws.
"The only thing we're not happy with - and the players themselves not - was in that last minute of the game, where we conceded the goal. We were angry at ourselves."
On the performance of Costa, who played in a protective face mask after suffering a broken nose in training on Thursday, Hiddink added: "The way he scored the first goal was typically him."
The Blues were 3-0 up inside 17 minutes and looked like champions, but that was mainly down to Newcastle's calamitous defending as McClaren's men lost for the sixth straight away game to fall back into the relegation zone.
The Magpies have more than two weeks to dwell on the defeat. They next play at Stoke on March 2 and will go to Spain for a training camp.