Quack, quack, Ducky.
From previous experience with a Merc that actually did seriously overheat its transmission oil I would say just take it easy and you should be fine Ducky. It sounds, if there is no smoke or untoward noises, as though you have a sensor glitch, just drive steadily and you should be fine. If in doubt at any point, just stop for a while.
Terms and conditions apply, advice given based on experience only and accepted at own risk,![]()