Palace made sure of a play-off berth as late goals from Mile Jedinak and Kevin Phillips overturned a 2-1 deficit and sent Peterborough down.
"The way that game went is about as ridiculous as the last few weeks have been," said Holloway.
"What I'm finding out really quickly about this group is the confidence they have.
"We got back into the game twice when we needed to after we had got ourselves into a pickle and it worked.
"Kevin Phillips has been doing that all his career and hopefully he can help us. We've come through it now and I think we'll be stronger for that against Brighton.
"I'm not celebrating because now we have to come up with a good performance to get past our arch-rivals."