The Buddies missed out on the chance to out further daylight between themselves and bottom club Dundee after Dougie Imrie's early opener was cancelled out by second half strikes from John Baird and Jim McAlister.
Now Lennon, whose side face Hearts in next weekend's Scottish Communities League Cup Final, is demanding his men come back stronger for the run-in between now and the end of the season.
Lennon said: "We have to regroup as a team.
"We need to find answers as to where it went wrong and try to improve for the next game.
"I made changes because there's been such a busy period recently and it's a big ask for players on the other side of 33, 34, and 35.
"But we have to try and finish this campaign better than we did last year which was eighth.
"That is a realistic aim as far as I'm concerned but it's down to ourselves whether we do that."
- Sports & Recreation
- Dougie Imrie