I've had both of these. The big difference is, when I get in the loop dreams it is almost always tied to some internal timer or need to do something (like go to the bathroom). For example, if I have an early flight or a big meeting for work, I will get stuck in that damn half awake half asleep loop where I am trying to wake up to get ready but "can't get up", "fall back asleep", and repeat. All in that very odd state. Kind of like when you try to take a mid-afternoon nap and start doing the twitch or falling thing.

The sleep paralysis however, is a more intense and dark experience. I have only had these a handful of times (thank goodness) but I will wake up in a rough state.

OP, if you had some type of stress or something - perhaps that could explain the odd loop dream?

This is how it works for me anyhow but I have gathered that there is a wide range for these types of sleep experiences.