Hi,
From what you've written, it sounds like you were correct to continue.
The Highway Code dictates that you should stop at an amber light, unless it's safer for you to continue (although most motorists seem to disregard this completely, and treat it as a green light lol).
Police cameras at traffic lights aren't actually "active" until the lights have turned red, and you would have noticed a flash if it had gone off (especially in the evening / night). Still, if you were flashed, then you can expect to receive a letter within about 2 weeks (if it's not your car, then it may take up to a month). After that, if you haven't heard anything, then you can take it as red you're in the clear.
If there weren't any cameras, then absolutely don't worry about it. No one would report you for that LMAO.
If you know something like this is going to cause you this much stress and anxiety, then either:-
a) allow more time to complete your journeys, so you're more vigilant (don't let other drivers bully you into making mistakes)
b) plan your journeys so you travel when traffic is lighter, so you don't have the pressure of impatient motorists.