Grealish was booked late on as Everton chased an equaliser, though ultimately lost 2-1.
Asked about the yellow card from ref Darren England, the midfielder said: "It was because he gave Kiernan (Dewsbury-Hall) a yellow card for taking a quick free-kick. I was like 'what are you doing?'
"We are losing, we want to get the ball back in play and he gives him a yellow card. It baffles me. So unheard of. I think he is on four yellow cards now and if he gets one more he gets banned.
"And where do you get three minutes (of stoppage time) from and one minute in the first half? I have never heard of that either. Come on. It is usually four or five minutes. It is what it is and we move on. I didn't even know he gave me a yellow, that is news to me."
