YOU SAID:

Today I ended up sleeping through the day

INTO JAPANESE

今日は一日中寝てしまった

BACK INTO ENGLISH

I fell asleep all day today.

INTO JAPANESE

今日は一日中眠っていた。

BACK INTO ENGLISH

I was asleep all day today.

INTO JAPANESE

今日は一日中眠っていた。

BACK INTO ENGLISH

I was asleep all day today.