Quote Originally Posted by sordid
1- You're psychological conditioning. If you subconsciously believe that cannabis is bad for you, it will not be an enjoyable experience. In time this may change, but don't force it.
I think he nailed it on the head here. Even if you don't realize it, you still have that conditioned state of mind in your subconscience, so there's always that little thing in the back of your mind saying "I don't know about this", therefore giving you bad experiences. Over time this should go away.