Spit up?

Amber

I've been slowly switching my 6 month old to formula by adding formula to pumped breastmilk bottles.

Now he also has a cold.

It seems like most times I feed him, he spits up after. It's mucusy and thick.

I'm just wondering if that's from the formula or his cold?

We're using Enfamil Gentlease and he usually sleeps from 7:30pm-1:30am for a feeding and then back to sleep until around 6am.