Throwing a wobbly
British SlangDefinition
To have a sudden tantrum—lose one’s temper or become very agitated.
Examples
"When the Wi‑Fi went down, he started throwing a wobbly in the office, shouting at the router like it had done it on purpose."
"Mum threw a wobbly when she saw the muddy footprints all over the new carpet."
"Don’t throw a wobbly—it’s only a tiny scratch on the car, and we can sort it out."