Scott Cuthbert was shown a red card midway through the first half as he was adjudged to have hauled down Keshi Anderson in the penalty area, before Luke Norris broke the deadlock from the resulting penalty.
The visitors doubled their lead shortly after the break when Chris Hussey curled home in fantastic style just after the restart, then they rounded off the scoring when Paul Mullin fired in from close range just after the hour mark.
Jones said: “I am bit shell-shocked really, because we went down to ten men and it was my decision to be a little bit more positive.
“When we have been down to ten men before we have clawed the game back. I am just disappointed with the result.
“Obviously we have set ourselves up – we won our home game against Colchester, we had two real difficult games in the away games. That sets us up nicely for our home game today.
“We started OK in terms of moving the ball well, when we gave it away they had set up to contain us on the counter-attack and I felt we were trying to force the issue, and the penalty changed the whole course of the game. It’s just disappointing.
“We are going to need to be right back at it on Tuesday night, because we have missed an opportunity today, we really have and we don’t want to lose any ground. We are losing ground at the moment on teams above us. It’s early days, we are six games in.
“But it’s very disappointing and I am very disappointed today in terms of our performance. We will dust ourselves down, we will be back in tomorrow and we will go again.”