Sleep Paralysis Or Something Else Maybe?

The title speaks for itself. My first story was about my girlfriend and her white spirit stalker. This one is about me and my bouts with what I believe to be sleep paralysis, and I'd like to have a second opinion.

This all began one sunny weekend afternoon. I was feeling sleepy, so I took a nap in my bedroom. My bedroom at that time had three doors, two walls with windows, three desks, a drawer, a closet, and a bunk bed. The bed was against a window, with all three doors facing me. The doors to the living room and the bathroom were open to let the air circulate, while the third door was closed and locked. It was a very warm day.

The dream:

I only remember a little of what happened towards the end of it: I was chased by a black dog with yellow eyes through a tunnel. I remember looking at it as it barked at me and then I woke up; or at least I thought I did, because I remember everything looking very foggy. I closed my eyes, because I still felt sleepy, and found myself in a new nightmare: something (looked like a gray, leathery, segmented worm with stiff tentacles attached to its mouth) had my entire left arm in its mouth and was swallowing it whole despite my efforts to shake it off. That scared me enough to wake me up; or so I thought, because everything still looked foggy.

The freaky bit:

I remember lying on the bed, out of breath, and staring at the bathroom. The girls' room connects to the bathroom, and it was pitch black, something that only strikes me as odd now for some reason; probably because what got my attention was a black mass on my drawer, staring at me with yellow eyes (it felt like a cat). I decided to roll over to my other side, except I felt my body move but my vision didn't. Right now, I was more "WTF?" than scared, so I rolled left some more and felt my knee go through the bed. I snapped back to my initial position and that's when I realized that I wasn't breathing.

I didn't have enough time to get scared by that, though, because something (felt like something) latched onto my left side and started pulling - my vision began going black on my left side, like I was being pulled through a door. I remember fighting to get back in my body, and after what seemed like forever, I snapped back in and woke up for real. I felt so weak, I was tempted to fall back asleep, but I stopped myself there and got up.

That one dream seemed to kick off an entire series of dreams that led to me waking up in a body that felt more like a sarcophagus, with me screaming and squirming to get moving and breathe. It eventually got so bad, my subconscious somehow developed a switch to wake me up if ever it felt like I was going to get sleep paralysis, and I've never had it again. That much I'm thankful for.

Now, why the "Something Else"? I've noticed that in those dreams that led to my sleep paralysis, I would start out running, then gliding, and then floating. Almost always in that pattern; the floating became my trigger to wake up, as a matter of fact.

Recently, I had another dream that felt like I was out looking for something. I remember returning through the warehouse next to our house, then following what looked like a vividly feathered dromaeosaurid towards the room where we all sleep in, going up the stairs, and heading to my bed. I woke up and felt like I had just come back from a long run.

Any thoughts? I'm more curious than scared, because I don't know if what I had was sleep paralysis, an out of body experience, or really crude astral projection.