Vommiting: You mentioned no other drugs, but did you have a ciggarette shortly before or shortly after smoking? Did you smoke a blunt? I know herb and tobacco don't mix well in my stomach and I have thrown up several times having smoked a cigarillio or chewed tobacco shortly after smoking.

Panic Attacks: Does your friend smoke constantly or did they take a break before smoking this most recent time. Anytime I smoke after taking a break, I'm always paranoid for the first 10 minutes and then it subsides.