Medical dictionaries generally define an overdose as
So in that case, Slinky is right. However, in the real world, nobody in a medical profession would use the term 'overdose' to describe getting too stoned and passing out - if they had to, it'd be a mild overdose followed by a clarification to ensure the term is not taken to mean potentially harmful or lethal dosage. Several members of my family are nurses and one's a doctor, I work in a lab and many of my friends are doctors and nurses from all areas of healthcare - not one of my colleagues, friends or associates would consider over-indulgence to be an overdose in clinically-understood terms.
By the way, that youtube clip reminds me of the early episodes from season 3 of The Inbetweeners - Will's "I'm in a bubble, and everything is flat. Time is going really, really slowly. I think I'm dying."