M.I.
if a first opinion doesnt give you the answer you feel comfortable with, get a 2nd and third and fourth if necessary.
vomiting up blood is NOT good, or safe, (i dont think) but i dont know anything about gastroschisis either.
i cant beleive they havent connected you with a specialist!
anyway, i would make another appt with the doctor, and ask him to refer you to another doctor or a specialist. DONT take no for an answer!
good luck.