It wasn't just three days, it was rising from Sheol-- Scott Smith offers a fascinating dive into this passage:
I called out of my distress to the Lord, And He answered me. I cried for help from the depth of Sheol; You heard my voice. You had cast me into the deep, into the heart of the seas, And the current engulfed me . . . Water encompassed me to the point of death. The great deep engulfed me, weeds were wrapped around my head. I descended to the roots of the mountains. The earth with its bars was around me forever, But You have brought up my life from the pit, O Lord my God. While I was fainting away, I remembered the Lord, and my prayer came to You, into Your holy temple. (Jon. 2:2-7)