By pushing Kirsty who was 9 months pregnant at the time, what the hell was Tina trying to prove?

Even if Kirsty had pushed her back, admitted the truth and "revealed her true colours", Tina would still have started it. She would still have lashed out at a pregnant woman.

Kirsty is manipulative and thrives on being in control and Tina just gave her the reaction she wanted.

Clever girl