What did I do to my leo???

[Pixie]

I was giving some food to my leos when I noticed that one of them seemed to have strange dark spots on her shoulders. I picked her up for a closer look to find dark scabs or gangrene! I am totally flipping out now!

A quick history of the past couple months with my leos: I had some treated and the others given a preventative treatment for worms with Panacur. This girl wasn't particularly affected but since she had some contact with an infected gecko me and my vet decided to give her a preventative treatment. She lost some weight due to losing her appetite over a few weeks and only recently started eating again. At first not much and very picky of which food items and after back to her old piggy self. She was brought back for a follow up visit at the vets when she still hadn't gotten her appetite back a bit less than two weeks ago.

She was given a shot of vitamins and antibiotics and I was given 4 follow up shots to give her. I was showed on how to do them, sub-cutaneously in the upper "arms". Since her first shots her appetite zoomed back to what it was and I can actually see a difference already in her tail. But today I find these "injuries" on her and I am freaked out. They are obviously due to her shots as they are in the exact locations that they were given.

Does anyone know what could have possibly done this??? Could it be the medication? Unfortunately, I don't know which antibiotic she was given as the syringes were preprepared for me and don't have tags...

Could it have been my poor execution of giving her the shots? I did it exactly the way I was shown and I do have some nursing training so I have a bit of practice on humans and understand the differences between sub-cutaneous, submuscular, etc...

Of course I am bringing her back in to the vet's first thing in the morning but is there anything I can do now? I'm thinking of putting some polisporin on but it'll be really hard... Since all the commotion with the shots she's afraid of me now... and I don't blame her, poor thing...

A very distraught Pixie...

I'll try to take some pics to show you what it looks like