Happy his stuttering team have another SPL game tomorrow in which they can atone for Saturday's disappointment against Inverness.
Happy it is not at Parkhead, where they have been at their most fallible in domestic games this season.
And happy that, in Hearts, they have an opponent who are sure to remind every one of his players how hard they are going to have to battle to retain their league title.
The pain – and anger – generated by the defeat to Inverness has not eased, and neither has the manager's annoyance at the reaction of some Celtic supporters.
However, Lennon – who is being made to wait for his 100th victory as Celtic boss – understands it is how they react to this setback that matters most.
And, while one point from their last three homes games in the SPL is never going to be an acceptable return for any Hoops boss, especially one overseeing their worst start to a league season this century, Lennon trusts his message of discontent has permeated the dressing room.
Now he wants his team to repeat the performance which saw them sweep aside Aberdeen at Pittodrie before the defeats in Lisbon and to Inverness.
That 2-0 win 10 days ago has helped keep Celtic at the top of the table, despite shipping 17 points in their opening 14 SPL games.
But Lennon is well aware that opposition sides are sensing an opportunity to damage them, and wants to rid their SPL rivals of that notion as quickly as possible.
He said: "I'm pleased we've a game tomorrow, even though I know it is going to be tough. We will digest all that happened on Saturday, then decide what kind of a team to put out for this game.
"I don't know if there is a vulnerability about us. I don't think there is. I think there's complacency, and we have to remedy that and eradicate it as quickly as possible."
Ironically, it is at what was for so long Fortress Parkhead that the flaws in Celtic's SPL make-up have appeared most obvious.
Lennon can't understand why this should be, but he is leaving no stone unturned in his pursuit of the answer.
"I don't know why this should be," he conceded with his usual honesty. "We have fluffed our lines a couple of times.
"I didn't think we played badly in the first half against Inverness. There was a good tempo to us, and our passing was decent, though I would not say it was as slick as it has been in other games.
"At times our movement was poor, really poor, and that needs to be looked at.
"The thing is that, between the games, I don't have time to work with the players. It's just game after game after game. So, it's a balancing act.
"But, Inverness at home ... we really should be doing a lot better than losing 1-0."
That was Celtic's second home defeat in the defence of their title, and the lack of goals – just seven scored in the seven SPL matches played at Celtic Park – is another massive concern for the manager.
"I don't know how much the Champions League games are taking out of them," he admitted. "I'm sure it is a factor.
"But I didn't think we were flat on Saturday. I just felt we were wasteful, and that is a concern for me.
"We were snatching at things. The ball was going over the bar, crosses were going out of play, and we were missing simple little passes on the counter-attack.
"Maybe that's mental fatigue rather than physical fatigue.
"We threw on three attacking players – Scott Brown, Lassad Nouioui and Paddy McCourt – to try and remedy it.
"We lacked a bit of creativity at times, and I'd hoped Paddy would bring that, but we did not get the ball out to him enough.
"Our crossing was awful at times, our set-plays were awful, lackadaisical, lazy, and we have got to start really smartening up, particularly in the final third, because that was poor on Saturday.
"It didn't go for us, and we have to make it go for us. We have to find that spark."
In the fire-cracker atmosphere always generated when Celtic visit Tynecastle, that spark could ignite Celtic's title defence.
The close proximity of the volatile crowd, as well as the physical nature of Hearts' play, ensures anyone giving less than 100% will be badly burned.
Lennon will take great care when deciding which players are best suited to this particular challenge, and is delighted he is getting some of the injured stars back for what is a crucial stage of the season.
The biggest test of all will come when Spartak Moscow arrive for next week's Champions League tie which could see the Hoops progress to the last 16.
Among those now able and willing to put their shoulder to the wheel of the misfiring Green Machine is Beram Kayal.
With Brown and Joe Ledley toiling to play with groin problems, and Victor Wanyama suspended for the Spartak match, his re-appearance in the starting XI is perfectly timed.
Lennon said: "He had a good game on Saturday, and looked far more like the Beram we know. That is obviously coming because of the number of matches he is now playing.
"Again, we have a number of very big games coming up, and I am sure he will feature in a few of them."