J.L.
the worst part is that the short 45 mins thatr he is sleeping at first is a quicl nap for hin so he is wide awake when he gets up. Try making his afternnon naps shorter. You might also want to try moving his first nap closer to the second nap so that you can take the second nap away. This might make him more tired at night. Is he eating more than usual? If so he might be going through a growth spurt. You could try adding a bowl of cereal to his dinner routine. The could also be teething, he might just be in pain. I hope one of these answers helps.