Do you think maybe Asa was offended? Rather than repenting, he strikes out—not that any of us would ever do that!
But, to me the interesting thing is that later, when he gets sick, he turns to—wait for it—medical science! He ignores God, even when he's in pain, because God offended him once. Before we cast a stone at him, though, take a look at our own medicine cabinet. What's in there? How often do we turn to it in our pain and diseases? Maybe, just maybe, we are as guilty as Asa?