Diamonds went into the clash at Kings Langley on the back of three successive wins but were beaten 1-0 as Jordan Parkes grabbed the winning goal from close-range with 11 minutes remaining.
With the likes of Liam Dolman and Jordan Macleod missing out due to injury, Diamonds were further hit by Ryan Dove pulling up during the warm-up.
It meant a fairly young line-up for the visitors with academy graduate Will Jones awarded his league debut as a second-half substitute.
And Champelovier admitted that while young players are being brought through, there will be “good days and bad days” to deal with.
“It was disappointing,” the head coach said.
“We have been on a good run and they hadn’t so we knew we wanted to get out of the blocks and put them under pressure.
“We did that in the first 10 minutes but we stopped picking up the ball in the midfield areas and I felt we got a bit bullied in there.
“We didn’t pick up enough second balls and it meant we weren’t able to get the ball into our frontmen enough.
“Kings Langley set up quite compact and you could see they were looking to nick something.
“To be fair to them, they did a decent job because they made it hard for us to break them down.
“We have had that good run and, during that, we have set standards pretty high.
“You have to try to match that standard every time and we didn’t quite do it on this occasion.
“We have got a young side, we gave young Will Jones a league debut from the bench and, at that point, we had five 18 year olds on the pitch.
“We want to blood these youngsters and bring them through and when you are doing that, you have to accept that there will be good days and bad days.”
Diamonds are without a game next weekend and aren’t back in action until they head to Bromsgrove Sporting on December 21.