Luke Berry had given the Hatters the lead in the 69th minute but Sam Gallagher replied for the away side shortly after, as Town remain 10th in the Sky Bet Championship.
Upon reflection on proceedings at Kenilworth Road, Nathan said: “It was a good game, I thought we were excellent first half and then we started first ten minutes of the second half superbly well.
“I was really pleased with the level of performance we had because we didn’t come here to contain Blackburn, we were on the front foot, I thought we were really brave in possession, especially first half and deservedly took the lead.
“I'm just disappointed with the goal. It’s a carbon copy of the goal we conceded here to make it 3-2 in the last game of the season, and that’s something we should have learned from.
"On the whole, I think it’s a fair result but I’m just delighted with the overall performance. We are competing and not just containing teams like this, because they are a good Championship side. Their ambitions are going up, budget, players, what they should do. They should be in the promotion shake-up, so for us, to be competing and to be doing as well as we are, I’m delighted with that.
“We’re not little old Luton, we’re finding our way with real ambition. They’re probably further down their journey than us, they've been a Championship side for three years and the group has been together for a lot longer.”