For some people the "paranoia" side effect of marijuana can be overwhelming. And some strains can produce a more "trippy" high than others. And then there is the fact that some people are nearly immune to marijuana effects while others can not tolerate it at all. I would suggest not trying it a third time.

That said, purchasing a basically illegal substance from a stranger is never a very good idea . . . which is why the battle rages over making it accessible to patients. In most patient co-ops you have patients growing it for other patients, which is considerably less risky. I would never get it from someone who could not identify the source or grower.

p.s. Marijuana is a "mood enhancer." that means if you are happy when you use it, you may feel happier. If you are depressed, it can deepen the feelings of depression. This is good to know if you use it medically, as there may be times when you wish to forgo using it at all because of the risk of intensifying an undesirable underlying mood.