As long as you control the set and setting for the trip, nothing terrible should happen. For me, nowadays, weed is more unexpected for me. Don't get me wrong; I've had my bad trips, but usually there was some factors influencing their quality that I didn't consider beforehand that I mention in the thread I linked you to before: right dosage, right administration technique, supplementation with anxiolytic amino acids and terpenes, choosing the right music, being in total darkness, etc.
The trip itself isn't supposed to be a joyride anyways. The good part is the remaining afterglow once the effects stop. So I wouldn't call them "recreative drugs" as many people wrongly assume.