The lighting herself on fire was caused by the mark on her arm, remember I said it would feel like the burn from the second time they touched. Her mind thought she was being attacked in her sleep, which is why her room was a mess, and why her shied appeared. Because she still felt it though, her dreaming logic was that she was setting herself on fire by the fire she created.
There were like five different symbolic parts xD
Hmm I think I'm gonna do that, just this once :)
Edit: By the way, in order to make sure I could remember it. I added the picture of their mark to Ciara's sheet, you don't have to. Just thought I'd tell you.