"It still haunts me, to be honest," Coleman told reporters.
"There's nothing worse than when you feel like you've let your country down -- and I did that in a big way... I was hanging on to my job.
"We had a room upstairs (in the dressing room) with no lights. I remember sitting in there with Kit Symons and Osian Roberts (his assistants) and I didn't want to come out and talk. It was the worst I've ever felt, the absolute worst."
Wales have never beaten Serbia, and Coleman, who will be without defenders Ben Davies and James Collins, warned that his team would have to be on their game to get win.
"Serbia are very aggressive offensively, they take chances," he added.
Austria are a point behind Wales, followed by Georgia and Moldova. The winners of each group qualify for the 2018 World Cup in Russia with the eight best runners-up advancing to a play-off round.
(Reporting by Debanjan Bose in Bengaluru)
Share
