What Could Cause Dehydration When Getting Treated For Diabetes, Hypertension And Fatty Liver?

Question : 53 year old Male Weight 243lbs Height 5' 10" Diabetes type 2 ED High Blood pressure GAD (according to my doctor) 2 inguinal hernias bilateral In February of 2017 I was peeing more that I thought I should. They took a urinalysis. It came back with a trace of blood. RBC 3-10hpf. With my age and smoking history they sent me to a urologist. The urologist did another urinalysis, rectal exam, CT scan of my abdominal and pelvic area, PSA blood draw, and a cystoscopy. They said everything was normal. To come back in a year for another urinalysis and rectal check. Both normal again. PSA was even lower than last year. Since last year I've felt they missed something. My doctor said I suffered from health anxiety. They put me on venlafaxine. I've had 3 chest xrays, another CT scan of my abdominal and pelvic area. They like the urologist all they find is fatty liver and small gallstones. I've also had 2 ct scan of my head. Showed nothing. I've had numerous blood draws. Everything was normal. That I was dehydrated. What could be dehydrating me? I have trouble sleeping at night. Could the venlafaxine make me sweat? I have a fear of having cancer. Do you think they have done enough testing? That I'm just worrying myself over nothing?