Stopping distance, white stop line.

[Baaaartz]

Quick question, I seen the lights go to amber, I was quiete close to the lights I probably could have made it through before it turned red (car next to me decided to do just that) however there was no one behind me so I decided to stop, I pressed my breaks a bit harder than usual and came to a complete stop, at that point my car went a little bit over the white stop line (roughly my 2 front wheels were bang on behind the stop line) the lights went to red, I have remained completely stationary, put my handbrake on until the lights turned green, then I have moved off.

Now Is that considered an offence? There was no way on earth I could have stopped any quicker especially with the roads being wet.

[Baaaartz]

There is a camera + the lights were still amber when I became stationary, they turned red when i was not moving at all, however a little bit past the line like stated above.