Is it possible to get diagnosed for Depression on 1st therapy session

Hi y’all,

Due to lots of stress in recent days, I was looking for Therapist. Found one based on Internet review and had my first session. I was little emotional and based on our conversation, They said it’s clear cut case of depression. They also prescribed some meds and said it’s very important for me cut some slack on my work for at least next 1 week. So still wondering can someone based on 30 mins conversation?