a storm in a teacup字面意思茶杯里的风暴，引申为小题大做，大惊小怪。

【例句】
The disagreement about pay is just a storm in a teacup.
有关工资问题上的分歧不过是小题大做而已。

I'm sure it will pass – it's just a storm in a teacup!
我相信这件事情肯定会过去的，只是小题大做而已！