On the face of it, if you caused an RTA, you are guilty of careless driving. Whether the police will prosecute is anyone's guess.
Historically, where the criminality/carelessness was relatively minor, as long as the insurance companies had everyone's details to sort out the insurance side of things, they would often take no further action.
If the carelessness/criminality was greater, or there were injuries, the police might prosecute for careless driving.
Nowadays, where cases are less serious, the police often consider that the offending driver would benefit from some form of course (which they get a kickback from the fee for). Whether the kickback is likely to influence their decision is not for me to say (although you might be able to guess what I think).
In general, if there is a possibility of any legal action for anything that you are involved it, always keep the best and most contemporaneous notes you can, and keep anything potentially relevant that you reasonably can. As DW190 used to say on PePiPoo many years ago "Blunt pencils are better than a sharp mind".
Otherwise, just wait to see what the police decide.
