DS throwing up again!

Will this ever end!  I think he is better than he gets sick!  He has been fine for over a week now and then bam it hits again last night.  We are thinking it was what he had for dinner though b/c there is no diarhea or fever.  He was screaming and I could not do anything right last night for over an hour and then he threw up on me and then again and like 5 times in a row.  Then played, nursed and slept til 730a (this happened at 11:30p).  I am at wit's end on why he is doing this.  He had Chicken parmesean (baked chicken with bread crumbs, spices, and spaghetti sauce) but I scrapped everything off but I am sure he got some spaghetti sauce and spices plus a piece of garlic bread that I did not think there was any garlic butter on it.  UGH!  Any one know of allergies to any of this?  Also, TMI but spaghetti noodles (his lunch) coming up is like worms coming from his belly, YUCKY!!!!