My son throws up all the time

My son is going to be 3. Starting when he was an infant he would throw up all the time. The doctors changed his formula to Similac Sensitve. That seemed to work. A few months ago my son started throwing up everyday. This went on for well over two weeks. He would throw up only at night near bed time. I started to wonder if he knew what he was doing and if he was doing it to delay bedtime. He stopped after about three weeks of every night. He had not thrown up for at least a month and then just this week he is back to throwing up. He throws up once or twice a night. He does complain of having a stomachache only during the day. Come night all is fine then out of no where he pukes. He doesnt complain of pain or say he is going to be sick. After he gets sick he continues with what he was doing like he doesnt know he puked. I have noticed that sometimes it has no smell and others it makes me want to get sick. He has had only random bouts of diarreah (diarrhea). I have also noticed that he stopped having normal collored bowels. His are like a sea foam greenish to light yellow. I am at a loss and Im worried for his health. Do you have any ideas of what could be wrong or am I just paranoid?

[Kevin Kennedy, Ph.D.]

You should be consulting with his pediatrician right away. This is not an emotional, behavioral or psychological issue. It needs to be dealt with medically.