Our DD, who's three weeks old, seems to have tummy pain around tea time each night for the past three days. She's been on Infacol for a while and we changed bottles as she kept throwing up her feeds. This has seemed to help but now she screams in pain and is very unsettled, we don't know what to do. Any advice? We changed her formula yesterday as she's been really up and down with her milk intake so thought this would help but it hasn't so far. Is a trip to the doctors needed?