The Whites could have taken a huge step towards securing a promotion place when they traveled to Eastleigh.
But despite leading through top scorer Ryan Bird, Dover came undone in the closing stages at the Silverlake Stadium.
Paul McCallum scored twice late on and although the Kent club remain in the top seven Kinnear knows it was a missed opportunity.
It ended Dover’s four-match winning run and the manager told Kent Online that his side didn’t get what they deserved.
“We were the better side by far, comfortable but we got a little bit carried away with ourselves,” the veteran manager explained to the website.
“We were creating chances, getting at them and it looked like we were going to get more but that's what happens with a young side they all get a bit over enthusiastic.
"I’m absolutely gutted because of the way we played, that was a different class to what we did on Saturday at Barrow.
“I am disappointed that we've lost when we've played so well – I'm less disappointed in that respect than Saturday because it wasn't really us.
“It was horrible and we didn't really look great but tonight we looked sharp and really up for it,” concluded Kinnear, whose team now face Tranmere Rovers at the Crabble on Good Friday.
PICTURE BY GRAHAM SCAMBLER