Erica is glad that John is there. I think that once she meets him, it'll be a lot easier for her to trust him. She's going to stop by his clinic, especially since Merlin told her that he was going to be away for a bit. She wants him to do some tests for her brain activity so that if Merlin's magic is fixing her she has at least proof that it's fixed, instead of just trusting that it is.

I think she'll still feel uncomfortable around him because he's a doctor and she's had so many of those in her life, but it'll be good for her to have someone she can trust that is a doctor.