Need Arimidex with HCG-Only?

My doctor prescribed me HCG as he wants to see if my testosterone natural production still has a chance to work on its own since I’m only 21 years old. He told me to take HCG 5000 IU per week without any estrogen blockers. Where I live there aren’t any good endo’s and I’ve relied on getting all my info online. Should I start taking Arimidex on top of my HCG to make sure my estrogen doesn’t get too high? (they sell Arimidex illegally without a prescription in pharmacies)
Also, how high can i expect my levels to go from 200ng/dl with only taking HCG? I am hoping for atleast 700-800

5000 way too much. SHould not be more than 500 a shot.
check this.

That’s insane dude, you’re not supposed to inject more than 500 iu’s at a time otherwise bad things will happen.

What will happen if I continue on this dose? (I kinda don’t have a choice as I get my shots at the clinic and my doc probs won’t listen if I try to convince him otherwise)