C.B.
I would go ahead and definately get the shots all at once. I know it is an awful lot for a baby and some do feel cranky and sore afterward( I have found that it depends on the baby not really the kind of shots) The consequences of him missing a dose of say like the flu shot will be much worse than the crankiness from getting the shots. I have an 18 mos. old boy and the thing he had a reaction to was the chickenpox vaccine. He was miserable for 2 or 3 days and had a slight bump and red welt on his upper leg for about a week or so. What also might help ease the discomfort is I always give a dose of Tylenol just before going to the Dr.s so it is in their system in case of fever or irritability.(I learned this a while ago with my first baby; Now almost 18 years old.)
And as for the formula I gradually aaded milk to his formula(my youngest was on soy formula) and by about two weeks he was completely on whole milk with no problems.