Matt Richards handed Shrewsbury a first-half lead which could have been doubled had referee Brendan Malone awarded a spot-kick, and a possible red card, after Terry Gornell was brought down by Alan McCormack with the Shrews well in control.
Instead, Robins substitute Alan Connell went on to bag a brace and win it for the hosts, leaving Turner perplexed. He said: "We couldn't believe that decision. Even the defender said he was ready to walk. Everybody in the ground thought it was a penalty and a sending off and no-one can quite understand how that decision wasn't given.
"Somebody suggested the referee was from Wiltshire. I don't know about that. I've never heard of him and I don't want to ever hear of him again. That decision was the big one in the game and arguably the only one in the game and he bottled it.
"He might have been overawed by the occasion or the size of the ground or something, but I cannot believe for the life of me that he hasn't given us a penalty and sent the man off. We've a good chance then of going 2-0 up against a side that's down to 10 men."
Swindon boss Paolo Di Canio added: "We are lucky. For the first 55 minutes Shrewsbury deserved to be in front. Maybe they should have had a penalty in the second half but we then went on to dominate the game."
