SPIT Up

My daughter is 3 months old. Last month her pediatrician switched her to Enfamil soy and told me to start putting cereal in her bottles to thicken it. She has always been a spit up baby but this last week she has been spitting up more than usual. I feed her 4.5 oz every 3 hours and she spits up constantly. I burp her at least 3 times during feedings. The last few days it’s just been running out of her mouth like water and she’s been extra fussy. What could this be? I have gone thru 4 bibs and 5 burp cloths in just one day today! She is also drooling a lot. Would this have anything to do with teething?