Pregnancy depression...

I never ever expected to feel this way. This was supposed to be a happy time, me and my husband planned this, its our first baby but I feel so depressed all the time. I dont understand why I'm feeling this way I'm just so sad all the time I feel so alone and hopeless and I just cry all the time. I'm taking care of myself and baby of course but I really have no one I can tell this too. My husband wont understand, my family lives on the other side of the world so they would just worry. I love my baby already and I just cant wait to meet him so I really dont get how I could feel both ways at the same time. Just wondering if anyone has ever felt this way and does it go away after pregnancy.