My baby has been very very grumpy lately... especially after he eats. He eats on both sides for quite awhile but can't seem to get enough because when he is done he keeps trying to latch on again and eat more and more and he cries because there is no more. He has been doing this for probably 4 days. I wonder if it is time for me to start him on some cereal? He is 5 months now. I don't know if he is hungry for more or what. Could this be a growth spurt time?