The trigger for the camera is usually an induction loop just beyond the stop line. You will have driven over this on red to trigger the camera. If stopping would have left you in the middle of the junction you wouldn't have triggered the camera I'm afraid.
They might send you the photo, but they are not obliged to unless you reject the fixed penalty (as material for your defence). I would advise you not to go down this route as it seems highly unlikely that you will win.
When renewing your car insurance, this will count as a driving conviction. You will have the offence code TS10 on your licence.
The points are valid on your licence for three years, but they must remain on there for four (although 'spent' for the purposes of totting after three). Your insurance company however will ask for details of convictions for the last 5 years.
Like I said, sorry to sound negative but that's how it is. I don't know you but looking objectively, it seems to me as though you could have and should have stopped. There's little you can do now except pay up and move on - like I said, put it down to experience.
Whatever you decide, good luck.