My 3mo always throw ups after feeding. his weight is fine and seems ok. sometimes it is watery sometimes just milk.

May be "overflowing": Some babies eat with such enthusiasm, they get overly full and spit up the excess. As long as your baby is growing and gaining well - and acting ok, he's probably just fine. Check with your provider at the next well-baby exam, unless you become more concerned before then. Sounds like you know what you're doing. Lgromkomd.

Likely nothing wrong: Most babies spit up some after many to most feedings. As long as it is not projectile vomiting and the baby seems happy, content, and is gaining weight appropriately, then the is probably nothing wrong. There can be simple and treatable problems like reflux going on though, so always mention something like this to your child's doctor at the next well child visit so everything can be checked out.