The Bulgarian champions made their bow in the European top-tier in a heart-breaking 2-1 loss to the Reds, who were back in the tournament for the first time since 2009-10.
Mario Balotelli opened the scoring in the 82nd minute, before Ludogorets thought they had snatched a point when Dani Abalo equalised in injury-time.
But a Steven Gerrard penalty would spare Liverpool's blushes in the third additional minute, denying brave Ludogorets a point from the encounter.
Coach Georgi Dermendzhiev said he did not blame goalkeeper Milan Borjan for conceding the decisive spot-kick, but was still disappointed to leave empty-handed.
"This is football. It is, of course, a bit bitter for us because of the result but I am not feeling unlucky or mad about it," Dermendzhiev told UEFA.com.
"The goalkeeper was upset after the mistake. That's a natural thing, but we are a very good team, we have a very good team spirit, and after the game his new team-mates and I said that it is not a big mistake and everything's fine, everything will be alright in the future.
"I am not blaming the goalkeeper, I am not annoyed or disappointed with him. This is a decision that has to be made in the moment, so there is nothing to attach blame to."
Defender Cosmin Moti said Ludogorets' ability to compete with Liverpool for much of the 90 minutes was a positive for their remaining five group games.
"It is hard to lose in the 93rd minute but I am happy that we played well and had a good game," the centre-back said.
"It is painful to lose in the 93rd minute but we finally realised how it is in the Champions League and we hope in the next game to repair out mistakes and try to do things better.
"If not the result, this game gives us confidence that we can have some great games."
Hamza Younes got the assist for Abalo's equaliser after only coming on in the 86th minute, and he said he was "proud" to have contributed.
"We played a very good game and deserved at least a draw but we didn't have the luck in the final minutes with the penalty," Younes said.
"I hope in the next game we can concentrate better and get some points."
