Help interpreting weird dream

I just had a really weird dream last night. It wasn't a typical nightmare, in that there wasn't really anything scary, but all throughout the dream I had the nightmare sensation of being powerless and afraid. This dream had quite a few different parts to it, so bear with me.
First I was at a hotel, coming home, and I was trying to open the door when a kid from my school comes up to me and says something like, "what are you doing?" I told him I was trying to get into my room, and he says, "Oh, okay," and walks away. I go into my room and see that there's another guy from school in the bed opposite mine. I try not to wake him up as I turn on the light to see, do some stuff before bed, and lie down. From there I was in a group of hippies who were walking across the USA. We were constantly doing drugs, including, but not limited to, weed, cocaine, and valium. We were always having parties, too, with lots of fireworks. I have never done drugs in reality before, so it was a strange experience. I'm not sure, but I think that what I was feeling could be classified as a "bad trip," where I was having hallucinations, seeing shadows that weren't there, jumping at every sound, and constantly being afraid. Then, the hippie march culminated in our arrival at a mountain range. We were about halfway up the mountain when suddenly a friend of mine started throwing the other hippies off of the mountain, to their deaths below. He was smiling as he did it. I turned around and looked at the side of the mountain, and it had eyes, very large eyes. They were arranged vertically, not horizontally. So there was one eye about level with my knee, and then another one a few feet up from there. I thought, "what if all of the continents are actually alive?" Then I was suddenly in a post-apocalyptic wasteland (All the evidence pointed toward zombies as the cause), but for some reason there was a convenience store. I went in with another one of the members from my survivor group- someone I am sort of acquainted with from school. She asked me to get her a toothbrush, only when she pointed at the item she wanted me to purchase, it was a toothbrush with all sorts of other things packaged in, as well. I told her I was short a few dollars to buy it, and she told me to put it in my pocket and walk out. It wouldn't fit in my pocket, because the package was a rather large square. I considered simply walking out with it in hand, but then I saw that the store had a group of armed soldiers as guards. I went up to the cash register, handed the cashier all the money in my wallet, and asked if he could spot me the rest. The guy asked why he should, and I told him that he should because we know each other, I was one of his regular customers. I actually believed this when I said it, but re-examining him after I woke up, I don't know him. He did lend me the money, and I walked out, toothbrush in hand, to a torrential downpour, only to find that my survivor group had left without me. I know that there were some other parts to the dream I am forgetting, but I only have bits and pieces. I remember something about a group of three zombies surrounding me and eating me before I woke up.
It actually doesn't sound so scary now that I'm typing it (except the part with the zombies), but at the time I was terrified and felt absolutely powerless.