to start to understand how badly something has affected you

开始吃苦头

I didn't read the contract fully before I signed it but I'm counting the cost now.

我没有通读合同就签了字，现在尝到了苦头。

We made a big mistake when we bought that old car, and we’re still counting the cost — it breaks down almost every week!

我们买那辆旧车时犯了个大错误，现在我们还在吃它的苦头——它几乎每周都出故障。