Let's start with the question related to receiving oral sex from your boyfriend two weeks after his tongue was pierced. The tongue heals very quickly so it would be unlikely for you to get HIV from him this way, if he is HIV infected. If he does have HIV, I would urge you to use dental dams for oral sex at all times. Even though the risk is lower than for vaginal sex, there is a risk.
You are right that hepatitis B is more easily transmitted than HIV. Persons with hepatitis have the virus in secretions (genital, oral, etc) just as is the case with HIV and so it is possible that sharing contaminated items to sniff drugs could transmit infection. The incubation time for hepatitis B is quite variable, ranging from as few as two to as much as 20 weeks. Despite all of this, I suspect your risk is low and in the absence of symptoms, I would not suggest a hepatitis test.
the first site is a study suggesting that hepatitis is found in nasal secretions, and the second puts people who have sniffed cocaine in a "high risk group"
As for dental dams, well, I tried one once and it was remarkably like receiving oral through a wetsuit. Of course, I think protected oral is pointless since the risk is really vanishingly small. Still, judging by your username, you might derive some comfort from the added protection. I would only add that if you haven't been vaccinated, ask your doctor about the HBV vaccine. That'll give you one less thing to worry about.
monkeyflower: thanks for the responce. I agree that I do need to get the HBV vaccine. The doctor recommended it as a child but I have always been afraid of needles, and refused lol. I am definatly going to get the vaccine now. It's too scary out there! lol.
Doctor: I have heard that Hepatitis B is usually defeated by a persons immune system, but I know that a person usually has to live with C. Is it possible for C to be transmitted this way? If so, it is less likely for C to be transmitted by sharing things in this manner than B?
and how quickly does the hepatitis virus, as well as the HIV virus die when exposed to air?