Graham Turner believes Shrewsbury missed a golden opportunity to pick up three points at Carlisle after they paid the penalty twice in a thrilling second half.
The home side hit back to earn a 2-2 draw which edges both sides a step closer to npower League One safety.
Lee Miller scored two spot kicks for Carlisle, the first coming after a Matt Richards free-kick had given Shrews the lead, the second arrived just when it appeared that on-loan Charlton defender Yado Mambo's first league goal had won it for the visitors.
"It was a missed opportunity," Turner said "I'm disappointed that we allowed Carlisle to get back at us after we scored.
"Judging from the reaction of the players the first penalty was a decision that shouldn't have been. The referee was unsighted for it and it was an amazing decision according to the players around."
Carlisle's second penalty was awarded when Miller was sent tumbling by goalkeeper Chris Weale, and Turner said:" It sounds as if there was contact, but the lad was already on the way down.
"Our downfall was to allow Carlisle to get into those positions immediately after we had scored. Settling down on the journey home we will probably consider it a point gained, but right now it seems like two lost."
Shrews' goals both stemmed from errors by Carlisle keeper Mark Gillespie, but Cumbrians' manager Greg Abbott was quick to defend the youngster, who was returning after a one-match ban.
"He will be playing at Sheffield United on Monday," he said. "He will be a really good keeper. He has made two errors, it's as simple as that, but he made two superb saves after that. He is a baby in football terms.
"There's a lot of tension around and we were good, bad and indifferent. The players are giving everything they have got and fighting for the fans. We have a lot of kids and they are learning all the time."