whole milk & gassy

My LO will be 1 in a week so I've started adding in small amounts of whole milk to her breast milk once a day.  For instance: 2oz while milk, 4oz breast milk.  Last night I switched and did 3.5oz whole milk and 2.5oz breast milk and she woke up multiple times during the night crying and gassy.  Is this normal or could this be attributed also to the messed up tummy that comes with teething?  I don't want to keep giving her whole milk if it's making her stomach upset