I thought it was kind of stupid - it's because he was trying to agree with everything I say.

He was saying that a doctor should put what their patient thinks, not what they think.
Not that I'm saying the doctor will always be right, but if someone with OCD thinks they have Bi polar - if the doctor knows this, what would be the point of giving them treatment for Bi polar, when it will just be a waste of time and money.

I hate when people agree with everything you say - when they don't actually believe it - why be fake.
I have 2 people doing this to me - a friend I was at school with and someone I talk to on facebook.