My youngest son is 4 months old. For the past 3 1/2 months he has been the sweetest little boy. Never cried unless he was hungry, wet or tired. He loved to play in his bouncy, swing, tummy time ect. The past two weeks he seems like a completely different baby. Out of nowhere he will start these crying fits where nothing calms him down. He'll scream, his face will turn red, he'll tense his whole body, his hands will make fits and shake. He isn't interested in any of his toys. He'll play in them for about 2 minutes to 5 minutes before starting a screaming fit. The only way to calm him down is to lay him over my shoulder wrapped in his balnket while I walk the floor. I spits up alot when he eats now and he didn't use to do that. When he was born he was born with fluid on his lungs. He was in the nicu fjor two days and released with no problems. At 5wks old they found he had a heart murmur. WE took him to a specialist who said it wouldn't cause him any problems. With that in the back of my mind I always worry that it could be something serious. We took him to the doctor 3 days ago and they thought it might be reflex. So they put him on Zantac, but that doesn't help. He still spits up and still has those crying fits at least twice a day.