I think they jumped the gun saying you were suicidal. I think the majority of new mothers would be suicidal by their standards. A baby is stressful and if you are depressed, as well, yeah, it's going to be worse.
I never took a survey, but my doc asked me questions and I was truthful with her about everything. She never once even suggested that I may be suicidal. I think you should get a second opinion and I think you should get some kind of help for your depression, but I don't believe you are suicidal. I think you COULD be if your depression gets worse, but that's true with anyone.
I don't believe the appointment should have been made for you. You have no babysitter, you are a new mother, you work...you need to make an appointment to fit into YOUR schedule, not theirs. If they had just called you to set it up, it would be one thing, but definitely not to make the appointment for you.