do sb's head in

to make someone feel confused or unhappy

让(某人)发懵;让(某人)不愉快

Getting up at four o'clock every morning was doing my head in.

每天早上四点起来让我脑袋发懵。

I've been trying to make sense of all these figures and it's doing my head in.

我一直试着弄清楚这些数字的含义，结果弄得一头雾水。