“I’m Under the Pump” Means “I’m Under Pressure”

“I’m under the pump” means that I am facing strong pressure or am in a difficult situation; it has nothing to do with standing beneath a water pump. Cambridge defines the phrase in terms of difficulty or feeling a lot of pressure, while Collins labels it informal and used mainly in Australia, New Zealand and South Africa.

It carries more external pressure than simply saying “I’m busy”, so it suits deadlines, a heavy workload or a sporting side struggling against sustained attack. A Chinese speaker should not translate 压力大 as “I have pressure”. “I’m under pressure” is standard, while everyday Australian speech can use: “Can we talk tomorrow? I’m really under the pump today.” The phrase is conversational; under pressure is safer in a formal report.

https://dictionary.cambridge.org/dictionary/english/under-the-pump
https://www.collinsdictionary.com/dictionary/english/under-the-pump