The Lions looked on course for victory after Chris Wood put them 2-0 up in the Championship clash but Brighton hit back hard and Kazenga LuaLua made it 2-1 before a late David Lopez penalty ensured the spoils were shared.
Jackett said: "Brighton are a very, very good side and probably the best team we have played.
"But I'm pleased with the performance and result. We created a number of chances in the first half and then we came under pressure but I was pleased that we took something from the game."
Wood is on loan from West Brom and Jackett says he is not sure whether he will be able to hang on to the 10-goal striker.
"I'm sure that Chris wants to stay," he said. "We are keen on him but we will have to see how it develops.
"I know that he likes it at Millwall. He has been playing and has been first choice.
"He is with us at present and his second goal was an absolute screamer. It's tough for him and he tired towards the end but we need to support him the best we can."
Jackett was forced to bring Jack Smith into the midfield before kick-off in place of the injured Andy Keogh.
"Unfortunately, Andy has a broken toe and we couldn't inject it," said the manager.
"We had to change the team because Andy didn't feel good enough to play but the squad has to adapt and Jack Smith came in and delivered an excellent performance."