Was driving along adn car just started losing power

Was driving along on the motor way at 80mph and car just started losing power and wouldnt respond and i pulled over to the hard shoulder. I had been trying to accelerate and overtake when this happened

After i stopped at hard shoulder engine didnt die and was still running. I gingerly drove off thinking it would just die but no it moved like nothing had happend and i managed to drive back home 20 miles. Its first time i had pushed it to 80 miles as drove only short distances to work and home

Seems it just didnt like being stretched to that speed which i know isnt much for a merc. I then tried flooring the pedal to see if turbo kicks in fine and it accelerated fine


What could be causing this please. only had the car 1 and half months and already love it so much