I've always wondered if the gun was out for some reason because it does seem so deliberate to go to get it, load it
I don't recall OP ever mentioning that he had to load the gun. I know that it shouldn't happen this way, but I honestly think that he kept it loaded. The fact that he kept it loaded with 'his father's' black talon bullets to me shows intent to use those bullets.
there are so many things that don't make sense to me I just can't stop thinking about them all.
UpNorth, this is my feeling too, but to my mind the so many things that don't make sense are all a part of OP's story.
My main thing remains 'why on earth did he think she was in the bedroom when he neither saw nor heard her there?'
'She was there just minutes before!' doesn't work in a scenario when a person can walk. It's not like he put down his hat and it mysteriously moved to another room.
He spoke to her and apparently it was completely normal, while he was walking around the bed to get his gun, for her to not respond to him. Even though he told her to call the police, she didn't start to do this. There was no response. None.
At that point, wouldn't any person just say 'Reeva?' to get that confirmation?
Is it feasible that an adult who knew that the other adult was awake and up, would move to another room so very quietly AND THEN, COINCIDENTALLY, the initial room is suddenly so dark that the other adult wouldn't be able to see them? Those two things had to have happened to make OP's story work. If there was enough light in the room to see - for example if there had been a light on an amp, he would have seen she wasn't there. If Reeva made even a tiny bit of sound when she was leaving, then OP would have known where she was. If OP had said 'Reeva, did you hear that?' rather than 'Get down and call the police', then he'd have known she wasn't there. If he'd have used his brain for a tiny amount of time to get the confirmation the way he knew he had to do, then she wouldn't have died.
I personally find it too much of a stretch. OP's hearing was good enough to hear the bathroom door opening, but not to hear footsteps on tiles, or the toilet flushing (or it was normal for Reeva not to flush - some people don't for a wee or at night). The level of silence was apparently normal - Reeva must have been in the habit of being totally silent and still, even when instructed to call the police. It must have been totally normal to wake in the middle of the night and use his girlfriend's jeans to black out the room entirely. If any one of these thing is not normal, then this 'terrible accident' might not have happened.
And then there's the gun. He said that he hadn't really intended to shoot, but before he knew it, the gun had gone off four times. One startle pull, fair enough, one and then three more? No. Also, bit of a coincidence that he's recently handled two guns with that much of a hair trigger. So this gun that shoots with little more than a thought was then carried through the passage, across the bed, out to the balcony, back to the bedroom where he must have put it down to put on his legs, then pick it up again, then back to the bathroom - all without it accidentally going off again.
That's easily explained - he absolutely and fully intended to shoot that gun and he did it totally deliberately. That part of his story simply 'could not be'. So why did he suggest anything otherwise? That, to me, is where OP showed himself to be an unreliable witness.
As to the screaming getting louder, if they were screaming in the bedroom, and then ran screaming into the bathroom, it may have sounded louder.