Okay, first off, calm down. Is the cat spayed? If not, that is probably why she is making all that noise.

Another reason could be a Urinary Tract Infection, hence the peeing everywhere. I think a vet visit is in order to rule it out.

You have to remember that this poor kitty just lost it's home to a fire and is separated from her human. Cats don't like change, which means she's probably stressed out to the max.

Try and put her in a spare room with a nightlight, food, water and litterbox and, if you have it, a radio tuned to classical music.

I commend you for helping this woman out. But you also have to take into consideration the cat's state of mind right now. Poor baby is confused and stressed.