Nathan Ashton fell under a tackle from Blackpool's Ian Evatt in the first half, and Scott Sinclair was booked for diving shortly after following a tackle from the same defender. Both incidents happened inside the Seasiders' box.
Warnock felt the second penalty claim was particularly justified and was scathing in his opinion of the ref.
"Unfortunately the referee hasn't got technology, he said.
"In all fairness Scott's feet are just too quick for him to see it. We had a look at half-time and the big man's leg caught his shin. The ref will recognise that when he sees it again.
"You could tell by the defender's reaction, he put his hands to his face because he thought he had given away a penalty. He was relieved to see the card for Scott.
"I think both would have been given had they been outside the box."