the way I see it, OP is definitely fixated on the 'it wasn't a woman screaming it was me' story - because the defence have to explain away the witnesses who say they heard a woman not a man.
so in the questioning earlier this is why he started talking about it not being a woman.
"OP: My lady, the sound of the gunshots was so loud, I was screaming, I couldn't even hear my own voice." reinforcing the I was screaming not Reeva
they need to ask, what were you screaming, as you were firing the shots? Certainly he can't have been screaming because he had shot Reva because in his version of events he didn't know it was Reeva, so what was he doing? Shooting and screaming through aggression?
OP: I discharged the firearm, I heard a noise and thought someone was coming out to attack me.
and screamed a lot.
also earlier in the questioning there is this exchange...
Nel: We are still here, at the considered. You considered and reasoned to be quiet.
OP: Because I didn't want to give my position away, my lady.
followed by
OP: I started screaming to Reeva to phone security or police.
on the one hand he has to be quiet because he didn't want to give his position away, on the other he was screaming to Reeva to call the police (This before he had fired a shot).