The Hatters had gone into the contest eager to make it six games unbeaten in all competitions and also atone for the 5-0 hammering they received from the Blues back in August.
Although they started fairly well, once Juninho Bacuna opened the scoring on 25 minutes, it always looked an uphill battle.
So it proved in the second period, Lyle Taylor scoring just 15 seconds in and then Onel Hernandez adding a third in the 69th minute.
Campbell said: “I thought we started the game well, did the basics right, but the goals meant it’s a tough one to take.
“We’re probably disappointed the way we conceded the goals, disappointed as a team, but that’s what we need to look at.
“We need to take these things on the chin, it was a poor performance, but we’ll look back at the positives and the negatives and make sure we’re ready for next week."
Hatters boss Nathan Jones stated in his post match press conference that he felt the protest from home supporters on 15 minutes, when the game was stopped due to tennis balls being thrown on from the stands, hampered his side’s momentum.
When asked what it was like from the players’ perspective, Campbell continued: “I don’t think we knew what was happening, but I thought we responded well after that.
“It was just a sloppy goal to concede and after the second one as well, the game was just a wee bit too far away from us, but we need to look back on it and try to learn from it.”
The timing of the Blues' second was to prove a real turning point as just after the restart, it meant any realistic hopes of a Luton comeback almost instantly evaporated.
Campbell said: “That’s the disappointing thing, you come out firing ready to go, try to make a game of it in the second half and then you concede so early.
"It’s a tough one to take, but it’s football and it’s part and parcel of the game.
"Sometimes it goes for you and some days it doesn’t, today just wasn’t our day.
"We can’t get too down on it, need to keep our heads held high and be ready to go again next week.”
Town, and Campbell himself, came close to making a game of it though, the midfield slicing one decent opportunity wide on his left foot, diverting another cross wide when making a run to the near post.
He said: “That’s one thing about the boys in there, we won’t stop fighting.
"We’ll keep giving our all, keep trying to get in the game, we had a couple of chances, but we will probably look at ourselves more in defending the goals and what we could have done better as a team, I think that’s where we’re more disappointed.”
Had Campbell found the net it would have been a fourth goal in eight matches, as he is quickly becoming an important cog in the Town midfield with his ability to get about the opposition players with real enthusiasm now boosted by becoming a regular threat in the final third too.
He added: “The manager gives you that freedom to go and play.
"We’ve got a good structure in the team, especially in the midfield with Pelly (Mpanzu) and H (Henri Lansbury).
"It gives me the license to go forward, hopefully I can keep trying to get in the box and get some more goals, but it wasn’t to be today.”