My 2 1/2 month old had been so cranky the last two days. He is exclusively bf and has been pulling away at feeding and crying. I take him off, try to burp him, and he screams. He has been spitting up thick clear mucous with white curds.. And I think he sounds congested. No stuffy nose, more like a rattling in his throat, but it's not consistent... I'm wondering if this could be due to the change in weather? I've taken him to the doctor a few times and mentioned him spitting up a lot, but it's ju...