R.A.
J., I responded to a similar post a few weeks ago. I pasted the repsonse below. Hope this helps.
we had similar, but not exact problems with our two, almost 3 yr old, son. It turned out to be enlarged adenoides. Call an ENT in your insurance network. Or I can highly recommend Dr. Jim Schroeder at Children's Memorial in Chicago (also takes appts out in Westchester). I won't go into details about adenoides and the havoc they can wreck on sleep, but either google it or look in Dr. Weissbluth's book which has a chapter about it.
Our son, had his removed about 3 and half weeks ago and the changes have been wonderful. He had trouble getting sufficient air because of his enlarged adenoides and this can cause sleep trouble. About 30% of children have this problem. It is quite common.