Ds will be 8 weeks on Tuesday. He was ebf for 6 weeks then we switched to formula for a number of reasons and he did great...downed 4 oz every 3 hrs from the getgo and was emptying the bottles. 4 days ago I started offering him 5 oz at each feeding, and at most feedings he was draining those bottles, too. Well the past 2 days he hasn't been eating as much. He is maybe taking 3 oz every 3 hours! Any idea what could be going on?