My 3 month old son has been having 9-10 green mucousy stools per day since he received his 2nd dose of the Rotavirus vaccine, Rotateq. It has been 10 days with no improvement. He is in a lot of pain before and during a bowel movement. Other than that, he seems perfectly fine. Is this a common side effect of the vaccine? How long will this last? What can I do to help him get better?