Your average driving violations like plate renewal, speeding ticker, unsafe move, tinted windows, muffler, etc.. stay on your record for 3 years since the date of CONVICTION.

A suspended license will stay on your record fro 6 years from the date of your CONVICTION.

I would suggest going to an MOT kiosk desk or the actual counter requesting your driver's abstract for $12 - it will show your record for the last 6 years, you may then see the EXACT date at which this happened, although I doubt it will show up on there since you say it was at the age of 15 when you did not have a driver's license yet. But it's a handy took either way to see how you've done in the last 6 years.

Note that any regular tickets that have been older than 3 years will not ofcourse show up.