My 20 Month Old Has Had What Ses Like A

My 20 month old has had what ses like a cold virus of some sort low grade fever-- took him to dr-- ear clear chest sounded good. Hecsaid it had to run its course. He vomited 2 nights in a row what looks like white cottage cheese smells awful. Happens after bottle milk and he falls asleep.
Should I be concerned with this thick vomit??? I never seen or smelt anything like it.