What Causes Appetite Loss And Mood Swings?

Hello. Recently, my boyfriend decided to just quit talking to me, and I have noticed a big change in myself. I ve lost my appetite. I have mood swings. For example, one minute I m fine the next I could cry. I feel angry and sad all at the same time. I can t concentrate on anything, because I have these thoughts of why he did this running through my head nonstop. So, my question is, is it possible I could be depressed? Or bipolar? Or is it normal to feel this way? Obviously I ve went through breakups before, but I ve never experienced just a huge change in myself.