Just a week after clinching a superb William Hill Scottish Cup triumph at East End Park, Accies were left disappointed as goals from Andy Kirk and Chris Kane handed the Pars all three points.
Midfielder Grant Gillespie did pull one back for the hosts but there was to be no late hero for Reid's side as they failed to make the most of Raith's match postponement.
Accies remain seventh in the Irn-Bru First Division standings and the Lanarkshire boss admits his troops were not up to scratch in the crucial midfield battle.
He said: "They played a different formation – they played three in the middle of the park and matched up against us. It was a battle in there.
"Last week we controlled the middle with our captain playing and they made sure we didn't do that.
"They sturdied it up and for 60 minutes we were second best, although I don't think they created much.
"I can't remember Kevin Cuthbert having too much to do but they were the better side.
"From the two set- pieces we conceded we ended up 2-0 down.
"We made a couple of changes and right from the changes we seemed to take off. I thought Gary Fisher was magnificent when he came on, and we started winning things in the middle of the park.
"We got the goal and could have had another couple. Gills [Gillespie] had a good move, the keeper made a great save, and we hit the underside of the bar. In the last 20 minutes we were on the front foot.
"If you look at the game over the first 60 minutes we deserved nothing, but in terms of saves, their goalie had more saves than ours, that is for sure.
"Overall, we had better chances and could have nicked the game."