two hands. river overbets. they bluffing or do they got it?

Originally Posted by IowaSkinsFan

I call both but I'm way more inclined to fold the 2nd one than the first.

could you elaborate if you don't mind. do you feel like the river could have made his hand in the second hand or that he may have been ahead the whole time with a better jack or some shit. and why are you more inclined to call the bigger overbet in the first hand?