For a couple of years, I experienced this exact thing. I would seemingly wake up and be unable to move. I could feel, see, and hear everything. It seemed so real. After struggling for a bit, I would finally be able to move. When I transitioned from the paralyzed state to the 'normal' state, it seemed flawless. There didn't seem to be any sort of 'waking up' involved, so I came to the conclusion that it wasn't a dream.
That is, until my brain made a critical mistake. One night, before falling asleep, I left an unopened bag of Doritos lying on the bed next to me. Well, after a few hours of sleep, I experienced the paralysis. It seemed authentic. My room looked exactly as it should, down to every last detail... except for one glaring oddity; The bag of Doritos was open, and they were scattered all across my bed.
As always, after struggling for a moment, I was able to move. Again, the transition from paralysis to normalcy was flawless. I was under the impression that the experience was real, until something caught my eye. The bag of Doritos was still sitting on my bed, sealed.
In my experience, these dreams were ridiculously realistic, but they were definitely dreams. Yours could be completely different; I don't know. It's just something to consider.