Spot on RAAFASA
Well worth owning up if you realise you bust CTA, let the controller know what level you're flying at and where you need to get to, so they can stop having to reroute traffic and know that you're on frequency and not going to create any further problems.
Sometimes controllers get a bit narky about it (fair enough), but all they really care about is actually knowing where you 'think' you're going and can get on with handling the rest of their traffic; their job is tough enough without you pretending you didn't do anything wrong.