How do you know if Allah is punishing you? When something negative happens then seek the forgiveness of Allah.

The condition of your heart will determine if Allah is punishing you or not. If your heart is made distant from Allah because of something that happened to you, then that is a punishment.

If your heart became closer to Allah because of something that happened to you, it was the biggest blessing.

Some people have a lot of money and a lot of wealth but this can drive them away from Allah. This is a punishment and not a blessing despite it seeming to be positive.

If you lost your job or had an accident or someone passed away, if it it made you come to pray, then this was the biggest blessing.