Davies was slow to react to Simon Davies's run and shot for the first goal, then brought down former Albion team-mate Diomansy Kamara for the free kick that led directly to Jimmy Bullard's winner.
"It's the ups and downs of football - the England call-up and then going to Fulham and losing the game," he told the Express & Star. "I thought I could have done better, but it just shows I've got more to do and I'm not going to stop trying.
"For the first goal I saw Simon Davies late and tried to react but he got there first. Then for the second I gave away a free-kick and I hold my hands up. I'm not going to hide.
"He (Kamara) skipped past someone and I thought: 'you're not going to get past me!'
"I thought if I didn't win the ball, it was better to get him, then we could regroup.
"I took the decision to win the ball or the man because I know 'Joe' can skip past people and score, but they did that anyway."
Davies denied any bad blood between the pair from their Hawthorns days, adding: "We're good friends. I've got his shirt. He was one of my best mates at Albion."