In the past three days, my daughter has started crying while feeding and gets squirmy. Sometimes she does need to burp or pass gas but other times, I can't figure out why she's so upset. She is on EASY and basically eats 2 ounces every 3 hours - sometimes 2.5 hours because of napping problems. She started on formula 2 weeks ago and hasn't had this problem until the past three days so I don't think it's the bottle or formula.
Is this a phase or something else?