The Ballymena man, who captained Ulster to victory in the 1999 Heineken Cup final, fought off an Achilles tendon injury to start the game but unfortunately he had to limp off nine minutes into the fray.
Speaking after the hosts' 26-17 defeat, he said: "In an ideal world I wouldn't have limped off but I have no regrets at all about playing.
"I played tonight for a certain reason and I think I achieved what I set out to do - to bring an end to what has been a fantastic 10 years (playing professionally with Ulster). I am not an emotional person but running out with my two children tonight was one of the proudest moments I have ever had.
"Katie and James have been so excited about it for the past 48 hours and it will be something they will always remember and something I will always remember," he explained.
Humphreys, who remains the Magners League's record points scorer (786 points), was philosophical when commenting on the injury that brought a premature end to his night.
"I felt the calf muscle snap just after I make a tackle on Maama Molitika and I knew that was it. Yes it was disappointing, but I knew all week that there was a chance it could happen," he added.
The former Ireland out-half was thrilled with the reception he received from the Ravenhill crowd - both before the game and when he was replaced.
"The crowd at Ravenhill has always been fantastic to me and it was worth coming out for that even if I was disappointed to only be able to play for 10 minutes or so.
"Rugby is the thing that has dominated my life for the last 15 years and I have enjoyed many good times, some ups and downs, and met a lot of good people.
"To play for Ulster was always a dream and the big matches I played in and the big European nights are something I will always treasure.
Meanwhile, apart from saying a fond farewell to Humphreys and a handful of other players who are moving on, Ulster coach Matt Williams was left reflecting on another game that saw his side looking tired and slipping off tackles.
"We missed some horrific tackles that cost us the game. Week in, week out, we are missing more tackles than any other team in the league," the Australian conceded.
"When that is the case you are going to lose games that you should win. We were creative, exciting and did a lot with the ball but our error count was awful. We should have won the game."
Agreeing that it had been a hard season for the players 'both internationally and with Ulster', Williams added: "In the lead-up to the game, we had to cut one training session short and cancel another altogether because the players were so tired.
"I think we are all happy that the season is over, so we can now draw a line in the sand and come back (for the first game) next September and start again."
He also feels Ulster can prosper next term, believing that the global trial of the IRB's Experimental Law Variations will suit his squad - one which will be bolstered by some strong signings.
"The new laws that will come into place will really suit us as we are not a big team, but we are a very fit team, aerobically strong and that's what the new laws will produce.
"The big guys will lose a lot of weight because there will be a lot of running involved so I think we'll be in pretty good shape in that regard.
"The new players I am bringing in will give us plenty of professionalism and there will be some changes in the staff too. It will be good to have some new blood on board," Williams said.