@chube, that was non-geek English.
Following from http://oxforddictionaries.com/
Definition of strop
[usually in singular] British informal
a bad mood; a temper: Nathalie gets in a strop and makes to leave
1970s: probably a back-formation from stroppy
Definition of stroppy
bad-tempered and argumentative: Patricia was getting stroppy
1950s: perhaps an abbreviation of obstreperous
As for "The dummy was spat and all the toys were out of the pram," just picture it. Oh, wait a minute, "pram" is short for "perambulator." I think US equivalent is baby-carriage? Also "dummy" is "pacifier?" Basically, it's comparing someone to a mardy kid.