The Blues defender felt Danny Cowley’s team were able to right the wrongs of last month’s controversial defeat to the U’s, after their 3-2 success at Fratton Park.
The Kassam Stadium reverse was shrouded in controversy with a string of bookings and Joe Morrell dismissed - along with a tunnel incident which led to the game being delayed.
FA and police investigations were launched in the wake of that clash, with Cowley admitting his team would use what unfolded to fuel their motivation in the return meeting.
And Carter, who smashed in Pompey’s crucial third goal, confessed he and his team enjoyed the moment as they picked up three points with a high-tempo and committed showing.
He said: ‘It was a brilliant way to put what happened at the Kassam right.
‘The result at the Kassam and all the events around the game seemed to be against us.
‘But that game showed how together we are, and I think we’ve shown that since.
‘The atmosphere was unbelievable here and the fans pulled us through again to get the win for us.
‘It certainly was really enjoyable - and hopefully there’s more wins like that to come.’
The Oxford win was the first Pompey had produced against any of the current top four in League One this season.
They had to come from behind to do that as Marcus Browne caught Cowley’s men cold in the third minute.
Pompey played with a determination and ferocity which the Fratton faithful reacted to as the rain teemed down.
Two goals in five minutes before the break turned the game around, before Carter stepped up with a superb 25 yarder in the 58th minute.
That proved of critical importance as Luke McNally pulled a goal back, before the Blues saw out a big three points.
Carter, who has established himself as a big favourite since his January arrival from Blackburn, confessed he’s never bagged a goal quite like the one he delivered to send the home crowd into raptures.
He added: ‘That’s the first time I’ve hit one like that - in a game or training!
‘All my goals last season for Burton were questionable whether they were mine or tap-ins.
‘Every goal counts, but when it goes in like that it feels that much sweeter.
‘I was supposed to be keeping the cover at the back, but I knew had time to have a pop.
‘I knew when it left my foot it was on its way - and luckily it went in.’