I had hypothyroidism and had to see an endocrinologist too. I only had one though. I didn't spend 3-4 hours the first time I went. She just did some random checks and that was it...it took maybe about 1 hr?

Aside from the weight gain and fatigue my symptoms were pretty mild. I' never had to take pills, I just had to do a lot of ultrasounds. Maybe the process is different if you're on the pills?