Graham Turner felt Shrewsbury were denied a "blatant" injury-time penalty in Saturday's thrilling 2-2 draw against Colchester.
Asa Hall, only introduced off the bench for the final 13 minutes, powered home two headers from corners by Jon Taylor in the space of three minutes to reel Colchester back in.
And Turner was adamant Town should have had the chance to crown their fight-back deep into stoppage time when debutant Jamie Proctor, on loan from Swansea, appeared to have his shirt tugged by Magnus Okuonghae inside the penalty area.
"All I saw was the lad pulling his shirt," Turner said. "It was so blatant it was unbelievable.
"As soon as I got in the corridor (Colchester boss) Joe Dunne said 'you should have had a penalty', but we didn't get too many favours on close decisions. Almost every one seemed to go against us."