Lately, Ive Been Hallucinating Every Time I Smoke. Anyone Have An Explanation?

Okay, I'd say I've smoked about 30 times in my life. I used to do it every week or so, but now that it's summer, I do it every night or two. I started smoking in January, and back then, I didn't really hallucinate at all, I would just get tunnel vision and things would kind of pulsate and zoom in and out. Now, it's different. I usually smoke about a half a gram, and about 10 minutes after smoking, the entire high gets crazy! It starts off with some closed eye visuals. Whenever I try and make sense of the image and identify what it is I am seeing, the image transforms into something else. After about 15 minutes, it's not only closed eye visuals I'm seeing, but also open eyed ones. I see these random patterns appearing that continuously morph into something else. I also get this sense that I'm viewing everything from a movie screen, it's kind of hard to explain. Everything also pulsates and kind of moves up and down. I tried watching a video on YouTube and whenever I focused on someone's face, their whole face would stretch out and then come back in and then it would happen all over again. It may sound like I'm complaining, but I'm not; I absolutely love these highs! They are profound and amazing, I just want to know why I am experiencing this! I've hung out with many different people while stoned, and none of them have ever experience any sort of hallucinations. I know what I'm smoking is weed and ONLY weed. Anyone know what could be causing this, or have experienced anything similar? Thanks!