YOU SAID:

I'm in me mum's car, vroom vroom.

INTO JAPANESE

私は私の母の車、vroomのvroomにいる。

BACK INTO ENGLISH

I am in my mother's car, vroom vroom.

INTO JAPANESE

私は母の車の中で、vroom vroomです。

BACK INTO ENGLISH

I am in my mother's car, vroom vroom.