Bolton fell to a 2-0 defeat against Coyle's old club, and the 46-year-old manager believes that his side let in soft goals and weren't potent enough up front.
"I felt we lost a poor goal," he said. "We had possession and gave it away cheaply and allowed a soft cross into box and either Sam Ricketts or Charlie Austin has bundled it in, it could have been either.
"We huffed and puffed without really imposing and I think we had one cleared off the line from Zat Knight at a corner but we certainly didn't create the goalscoring opportunities that I would have wanted.
"I'll have to look at it again but Martin Paterson looked a couple of yards offside when the ball was knocked to him by Charlie Austin. I'll need to see that back and it didn't help but in the second half we were looking to react better to that."
Coyle was given a negative reception from the home fans due to his switch to Bolton, but insists that the abuse does not affect him.
"The atmosphere was what it was," he added. "Whatever happened today was never going to spoil my view of this club.
"We used the fans to great effect when I was at the club so I can hardly moan when I leave and they react like that."
Bolton will be looking to bounce back from their opening-day defeat when they face Derby on Tuesday night.