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Please! My son is almost 10 weeks old. We just switched him from Enfamil to Goodstart. Since then he's been spitting up.. and not NORMAL spit up. Like projectile vomit. It's really beginning to worry me. The doctor keeps telling me it could be formula but a reaction from his shots from LAST week. I've been asking for opinions and advice elsewhere also and I've heard it's formula change to an allergic reaction to the formula. I don't want to keep switching him. Please, any helpful advice is welcomed!