I (try) to write fiction stories. Specifically, mystery/thrillers. I am currently working on a story with two main characters. I'm keeping my chapters short, about 3,500 words each. I make an effort to change POV now and then in order to allow the main characters to disclose their emotional responses to different situations. It also makes it easy to describe physical attributes of each character and how they feel about each other since they are lovers. I've been thinking about doing a few scattered chapters in first person. My question is - am I already confusing the reader by changing POV? If this is true, would it be a real disaster to do some chapters in first person?