YOU SAID:

I had a sandwich in my head

INTO JAPANESE

私の頭の中にサンドイッチを食べた

BACK INTO ENGLISH

Ate a sandwich in my head

INTO JAPANESE

私の頭の中でサンドイッチを食べた

BACK INTO ENGLISH

I ate a sandwich in my head

INTO JAPANESE

私は私の頭の中でサンドイッチを食べた

BACK INTO ENGLISH

I ate a sandwich in my head