Following the dismissal of his own player Manuel Pascali last week under almost identical circumstances, Shiels took no delight in Stephen McKenna's early exit as his side went on to complete a 2-1 win at Rugby Park.
He said: "The Football Association must have changed the rules on tackling and I am trying to figure out what they are. I couldn't see anything wrong with the tackle and I would be very disappointed if I was with Queen of the South.
"It made it more difficult for us as it gave us more space and time on the ball, almost a reversal of last week when Manuel Pascali was sent off for a similar kind of challenge.
"The boys kept the ball well but we had a lack of penetration as we had too many options.
"I am delighted though to get through and thought it was well deserved. We started last season's league cup run with a victory over Queen so who knows where we can go from here."
Queen of the South boss and former Killie hero Allan Johnston said: "It was very frustrating.
"It is a hard job for referees but it just looked like a strong tackle to me. I didn't think it was a two-footed tackle and he has won the ball with one foot and maybe caught the player with the other."