Welcome to the forum. Thanks for looking at other questions similar to your own.
And of course the answer is the same as you expect. Sharing cocaine snorting tubes may carry some theoretical risk for transmission of blood-borne infections, but I am unaware of a single well documented case in which it actually happened -- i.e. no proved transmissions of HIV, HBV, or HCV and would not have recommended testing for any of them. In any case, your negative HIV and HCV tests at 6 weeks are definitive. Co-infection does not delay antibody detection for either infection.
I don't think it's worth the time and energy to track down your classmate to ask about HIV or hepatitis status. Even if positive, there is no significant risk. You can and should continue unprotected sex with your wife without worry.
I hope this has been helpful. Best wishes-- HHH, MD
Yes, this was very helpful. I am just very excited to start a family and the idea that this dumb thing I did could jeopardize it made me insane. Deep down I knew I was being dramatic but I did the worst possible thing and started researching the internet. I take your expert advice and not worry anymore over this and enjoy the summer. All the best.
Thanks for the thanks. Have a great summer yourself.