HELP!!! Did i do more bad than good treating her?

-2 1/2 year ol RSL hen.
-Respiratory issues - air sacs sound like a paper bad being crushed when she breaths. Hit her up with Tylan for 4 days. Nothing. waited a few days, went to Pen.G for four days. Nothing.
-Has always had brittle feathers and a loss of feathers
-Made her a felt 'jacket' or pinney for her to wear - it's cold and snow and i wanted her to stay warm with a bare back and starting bear neck. Watched that it was lose enough and didnt hinder her crop. She doesnt mind it at all.
- flock started to get runny nose and swollen eyes. Bought LA-200 gave them all shots of 1CC yesterday afternoon

by 7:00 PM when i checked on them to tuck them in she was sitting on a lower roost and was fluffed up. I picked her up and can tell she wasnt feeling right. I took off her pinney thinking it may have been to tight and she couldnt eat all day? Her crop was empty as well. When I put her down she had some warm oatmeal and started doing this 'thing' with her neck and head. Moving it around in circles stretching. I got some water down her thinking maybe she was having trouble getting the oatmeal down. I got some watered down oatmeal down her. She sat down on the roost and fluffed up and started to sit tilting to the side. NOT right. So I brought her into the house for an hour or two and sat her on my lap.

I made her a scrambled egg and she ate some then started to do the neck thing again. Awhile later I took her back down to the coop to be with the others. This am she is standing on the perch and does not feel well, but I did not see her neck do that horrible stretching and circling thing. Has anyone seen anything like this? It would look like if we stretched our head forward and then made a complete circle in the air with it.

Could I maybe have hit a muscle in her neck with the needle when i pulled up the skin at the nape to gave her the shot and it just hurts like when we get a bad shot?