YOU SAID:

I banged your mom last night on accident

INTO JAPANESE

私は事故で昨夜あなたのお母さんを叩いた

BACK INTO ENGLISH

I hit your mom last night by accident

INTO JAPANESE

私は偶然に昨夜あなたのお母さんを打った

BACK INTO ENGLISH

I accidentally hit your mom last night

INTO JAPANESE

私は誤って昨夜あなたのお母さんを打った

BACK INTO ENGLISH

I accidentally hit your mom last night