Switching Formulas (soy)

aveeh

We switched DD from Enfamil Gentlease to Enfamil Soybee per pedi recommendation because she has had tummy issues since she moved from breastmilk to formula.  She was never constipated on Gentlease, but she had a rock hard belly and was very fussy after eating.  When she pooped it looked normal and she was very smiley after the deed was done so we thought even though she wasn't constipated maybe she was having some troubles.

Its been 3 days on soy and her one and only poop was a little nugget.  Is this a normal switching formula reaction or a sign she shouldn't be on soy.

Any advice?

TIA!