Edited by sarahlorrain - 5/6/16 at 6:57am
Can you post some photos of how they are puffed out?
Any chance they got into something moldy, rotten.
Do they stay with the broody and are they free range?
What do their crops feel like?
Are they eating/drinking?
Puffed up and standing around could be a sign of Cocci. While medicated feed gives a very low dose of usually Amprol, if they are already exhibiting signs you will want to treat them with Corid. Dosage for Cocci is1 1/2 teaspoons Corid powder per gallon or 2 teaspoons of 9.6% Corid liquid per gallon Give for 5-7 days - make sure this is the ONLY water available during that time period. Mix a fresh batch at least once a day. It won't hurt the broody to drink it as well.
The vomiting sounds more like a crop issue though, while they may have access to dirt, in this case I would provide them with some chick grit (crushed granite), it's possible that they may have eaten something that is impacting the crop and they are unable to digest/grind their food properly. Make sure they are drinking plenty of water.