needing some advice

How do I go about talking to my doctor about me thinking I may have depression? I was told growing up I had all the signs of depression but never got the help for it, then I had post partum with my first. Now I'm 26 weeks pregnant and things just seem to be getting worse for me. I don't know to bring it up to her. My husband says  I'm probably not depressed and that it's just me stressed out... could that be all it is?