My problem is Clark/Superman's seeming lack of seriousness about kryptonite. He told Lois in the previous chapter he doesn't know if it can kill him!? Shouldn't he look into this. Shouldn't he know?!

He admitted that the baby Kal may have dies because K weakened him and other factors killed him. So at the least K can indirectly kill Clark.

Lex will know for sure soon enough.

Superman's naivete will ultimately lead to his death. Being an innocent Boy Scout believing the the goodness of everyone won't cut it in a world with larger than life villains like Lex.

Lois needs to knock some sense into him or he won't be long for this world.