He told the Sunday Mirror: "I wouldn't change anything, trust me. I played last Saturday against Sunderland, scored the only goal of the game from the penalty spot and we picked up three valuable points, which moved us a step closer to Europe.
"I would have rather played for Pompey than sat on the bench at Wembley for the Carling Cup Final."
Defoe added: "If I look back I think I've wasted 18 months of my career.
"I'm still bumping into a lot of Tottenham supporters now who still can't believe I wasn't getting more games and are disappointed I left."