Depression?

So I know there’s postpartum depression but can you get depressed while still pregnant? I’m currently 34 weeks and 2 days and for the past few days I feel like my emotions have been everywhere. I feel so alone and overwhelmed. It was recently my birthday and all I asked for was a dinner date either at home or out at a restaurant I didn’t even care if it was a diner since breakfast is my favorite. And my boyfriend left to go out with his friend on my birthday and the following day went ice fishing. I tried to talk to him about how I feel but it ends up being an argument and then I just feel worse in the end. I’ve never had depression before so I can’t tell if it’s just my hormones acting up or not. My doctor always ask if I feel sad and I always say no but I have an appt this Thursday and I think I should tell them but again at the same time I just don’t know if I’m overthinking all this