Shit, my first high was one of the most scary experiences of my life. That night I took more hits than I ever have in one sitting after that, because I didn't know how much I should have smoked or what to expect. I gave it another try, and I have loved it ever since. By the way, following after my first time, up until my second time, I was pretty sure I would never do it again. I thought it wasn't for me, but I found out otherwise. You should try it at least 2-3 times before you decide it's not for you. Like others have said, you didn't know what to expect, and you didn't know how much you should have smoked to reach a pleasant, desired effect. As you get more experience, you can gauge this while smoking, and decide when it's best to quit. Even as someone who loves ganja to the point of passion, I can tell you that I can hardly smoke a whole bowl of high quality sinsemilla to myself. Yes, I'm a lightweight. But as a lightweight, I make sure to pack only what I plan to smoke, because I've learned to figure out how much I'll need to reach that desired effect. It's better to pack it/roll it too small than to pack it/roll it too big and think that you need to finish it all off, and then get too high for your level of experience.

Like that one guy said: Take a hit, wait 5 minutes or so to gauge it, and take another. Wait 5 minutes, and if you want to be higher, then keep doing that. Otherwise stop. This makes it difficult to go beyond what you feel is comfortable.

Once you get the general idea of how it feels, you'll be able to see if it's for you or not. Otherwise you can always switch to meth.