Movie about a marriage in Australia and drugs and a sheep

I’m looking for a movie based in Australia a British guy is about to get married with an Aussie girl. His friends are coming to be best men for his marriage, one of them is buying drugs from a guy on the road, but he swap his bag with the dealer’s bag. Tons of drugs are in this bag and the sheep swallows a few bits. One of the best men is depressed following a harsh breakup with his girlfriend.
Can’t remember the name but I know all about it

Is it A Few Best Men?