Bailey apparently is not over that whole bit with her infected some of her patients. That's what I believe this stems from. She was so worried about infection that she was seeing imaginary bubbles. I don't like how she's treating her husband. She's acting like she doesn't want him there at all.
Christina and Meredith really are at odds. I couldn't believe Christina took over that machine from Meredith, setting her back months in her research. That machine wouldn't even be there if it weren't for her. Ugh.