Prostate testes pain... why a thyroid test?

I posted this on the thyroid forum already though it's maybe more appropriate here.

The last two months I've had groin pain (lymph nodes I think though I didn;t palpate them. Was sent home 3 days in a row because of it as had to lie down as couldn't sit or stand...so I lost that job. As the groin pain has settled it's apparent from the pgeneral pain and tenderness to touch that my testicles, prostate and urethra are swollen. I've had a persistent cough too which seems to antagonise the pain.
The GenitoUrinary Doctor suggested to get my kidneys, liver and endocrine system checked by my own Doc. I went to see him and he ordered tests, just I had to make an appt with the nurse.

I went today to get the blood taken. Seems Dr has ordered CBC, liver, kidney and THYROID tests.

I'm probably missing something but isn't thyroid the other end of my body from prostate or are thyroid and prostate hormones linked much?

I can tell there is some relationship with some glands as I've had burning hot feeling at back of head (is that Pituatory gland?) and chills from there to my prostate/testicle/perineum area. What are the links?