Blisters on comb

[AbiandAmi]

Hello
I have found some strange blood blister looking things on my hens comb. Does anyone know what they are?? I know it is kind of hard to see in the photo but they are like little tiny lumps that look like blood blisters. That is the only part of her comb that has it. I noticed them on Friday and it is now Monday night and no more seem to have grown.

 

[MarcoPollo]

Other chickens probably pecked at her comb. My hens have this from time to time also. I am pretty sure it's from another hen biting or pecking.
I get bitten every now and then by one of my hens and the blood blister is very similar. Only difference is when I notice these on my hens they usually have fresh blood at the site; the blood will eventually dry up, darken, and go away. When I'm bitten, usually the skin on my hand doesn't bleed but just has a blood blister under the skin.