I drove hospital today worried about damaged intestinal lining from uncontrollable puking of green, black material.
I withheld my information to the doctor and nurse, including the part about my substance abuse (using illegal drugs)
The night before. While I was waiting for my diagnosis behind the curtain, I could hear all the employees making fun of my substance abuse,
Making cruel jokes, even calling me a "raver, e-tard."

Probably not a HIPAA violation since the talk was among people providing your care, not 3rd parties. And while it may have been cruel, you brought it on yourself by not providing the doctor with an accurate medical history (very dangerous)!

However, it was unprofessional behavior and you can report it to the hospital administrator.

It is unprofessional to say the least, but not a HIPAA violation. It is extremely important that your health care providers know ALL of your medical history, including your addictions.

What would have happened if they gave you a medication that counteracted with the drugs you use? You could have died and in that case it would not have been the fault of your care providers because you weren't honest with them.