YOU SAID:

I came in her so hard

INTO JAPANESE

私は一生懸命彼女に入った

BACK INTO ENGLISH

I entered her hard

INTO JAPANESE

私は彼女に一生懸命入った

BACK INTO ENGLISH

I worked hard on her

INTO JAPANESE

私は彼女に一生懸命働きました

BACK INTO ENGLISH

I worked hard on her