For the past week I have been feeling weird. It's a coincidence since I smoked weed exactly one week ago and about 15 minutes after I smoked I felt like I was going to die. I started shaking and felt dizzy.. I was thinking the weed could have been laced with something. After that, I haven't felt right since. I don't know if it's just a coincidence. But I have a little head pressure when I move my head up and down, and when I look around, it seems as if things are off balance and as if they're moving but it's only my head that's really moving. Could this be permnanent damage or brain damage? I'm really scared, I'm a hypochondriac.. what could this be?