British Lions rivals Jones and opposite number Ronan O'Gara enjoyed a fierce kicking battle royal at the Millennium Stadium.
But it was the visitors' number 10 who carved his name in Irish rugby folklore with the winning drop-goal three minutes from time.
Jones, 31, said: "I can safely say I've never been involved in such an emotional and dramatic last five minutes before.
"It was amazing and I experienced the whole range of emotions in a short period from when my drop goal went over right up to the final kick to win the game - it was mad.
"It was a bitterly disappointing experience for me to say the least and it just did not go our way.
"I did not strike through the ball and got under it which was frustrating.
"When you are out there engrossed in the whole affair, you just think of the process you need. I knew it was a long kick but I was happy with the way I was striking the ball.
"It was going straight and I was happy with that but I did not strike it as well as the one in the first half and sadly did not have enough energy behind it."
Jones scored all the Dragons' points in response to two quick-fire second half tries from Ireland skipper Brian O'Driscoll and Tommy Bowe.
But his dramatic last-kick-of-the-match-miss was possibly the only moment lacking fizz in a brutal encounter which saw the vast majority of players book their seats on the plane for this summer's British Lions squad to South Africa.
And the experienced Jones, capped 80 times by the Dragons, reckons the Emerald Isle were full value for their first Slam success since 1948.
Jones said: "Ireland are worthy champions. We know how hard it is to win the Grand Slam and they deserve it."