Cold and being sick after every feed

[Rosebel]

My LO is 12 weeks old and has a horrible cold (caught from his sister). Feeding and sleeping is all over the place but that's okay. But he's being sick after every feed, not just a bit but quite a lot. He always cries for a few seconds then is sick and okay again.
Tried smaller, more frequent feeds, keeping him upright, feeding slowly with breaks but he's still sick.
He used to do this as a newborn but the above worked. I know why he's being sick but is it normal? Do I need to call a doctor?