Peter Taylor insists Gillingham deserved a point after seeing leaders Leyton Orient snatch a last-gasp 2-1 victory at Priestfield.
Frenchman Yohann Lasimant nodded home his second goal of the season in injury time, three minutes after coming off the bench, to give Orient a first league win in five - which moved them back to the top of the table after Brentford had temporarily overtaken them earlier in the day.
Adebayo Akinfenwa put the Gills into a fourth-minute lead with a looping header before Elliot Omozusi saw his spot-kick saved by home keeper Stuart Nelson - not the first time this season the O's have missed a penalty.
But on-loan Orient midfielder Marvin Bartley restored parity with a header 20 minutes from time before Lasimant grabbed the winner after Leon Legge had cleared his initial effort off the line.
"I'm very frustrated. It was a bad goal to give away at the end," Taylor said. "To concede so late is very frustrating, but it's not the first time it's happened.
"When you're playing against a top team in the division and you put in a good account of yourselves, you should be pleased. But the final minutes were very disappointing.
"There were a lot more positives than negatives. The football we played at times was very good, we created a lot of chances, some of them very, very good.
"We deserved to score early on, we were very positive. To be fair, we started well in the second half and if we had scored then it might have been a different situation.
"The spirit of the players is excellent, they're taking on what we're trying to do and we're getting better.
"We played against Leyton Orient, who have had a marvellous season so far, and we gave them a really good game. I think we deserved a draw."