More or less yes you did American English correctly. More often I just refer to them as semis without adding the truck part, some also call them tractor trailers. It was clear what you meant though so only need to change it slightly if you are going for full American English
Yes, the brand Tupperware is an mlm and sold directly by sales people. Back in the 50s and 60s Tupperware parties were a thing.
The confusion is likely the whole q-tip/Kleenex thing. We call it all Tupperware but really it is not Tupperware brand most of the time