English Translation
I was extremely tired.
FYI: ひどく or 酷く is used exclusively in a negative context. 酷い（ひどい）as an adjective means “terrible/awful”.
You can NOT use ひどく/酷く as an adverb in the following positive sentences:
This device is extremely accurate. ==> この機器は非常に正確だ。（このききはひじょうにせいかくだ）
Mary did extremely well in the exam. ==> メアリーは試験の出来がとても良かった。（しけんのできがとてもよかった）