Even Greener Pastures

You probably know this already, Nikola, but 'be sick' only means 'throw up' in BrE.

"I was sick yesterday" (AmE)  = Stative verb, meaning "I wasn't well", in general terms
"I was sick yesterday" (BrE)    = Active verb, meaning "I threw up"  ( but may otherwise have been fine - only refers to a single incident).

Here's another one for the list... 'chunder'.