Injured hen

I have an injured hen and I have a ton of questions. I'm new to this chicken keeping thing.
Is this bump on her beak normal? None of my other birds have anything that looks like this. Does it look like the others have been attacking her? I found blood on the wall of the coop up by the roost. (Side note it's been really cold here so some of the hens got a little frostbite but the lower scabs on her comb look like peck marks to me) She's been acting lethargic for a few days. Yesterday she was limping so I brought her into my heated garage and I just gave her a bath today. She had poop up under her wing and on her side but besides that I can't find anything wrong with her. Any ideas what is going on? She's last in the pecking order and the others don't let her eat until they are finished. Will she ever be okay with them or should I just find her a new home? Maybe once she is strong and healthy she'll do better with them? Also, I know it isn't good for them to be alone, how long should I keep her inside, do I need to worry about her going from a heated garage to freezing temps? Okay, that's a lot of questions and I'm sure I could ask more. Any help appreciated! Thanks! A little background info: I live in south central Alaska, it's about 12 degrees F today but it's been in the 40's until just recently. A few weeks ago it's was in the negative temps like -10 or so that's when they got the frostbite. She is about 6-7 months old and is very skittish. She seemed to enjoy her bath and scrambled eggs today.

Hey! She might never become accepted by the others, have you had them all since chicks? I do not know why, but sometimes a hen is never accepted. The heated garage to the cold coop should not bother her, but putting her back with the others might not be a good idea. Could you put her in the he coop but keep her seperated, so the others do not attack her?