She has experienced "sleep paralysis". This was not "sleep paralysis".
And you are basing this conclusion upon what? Her own assertion? Her feelings on it alone? Yours? Or upon a professional opinion or two, or three?
- There is more than one form of sleep paralysis. Just because one occurrence didn't match the rest, does not mean it's not sleep paralysis.
- And as well, the fact that she has experienced sleep paralysis before and perhaps since makes it all more likely that this event also was sleep paralysis.
Let me ask you if this is just someone's mind playing tricks on them: There is a house with a side door that is open. Someone walks by, in the daytime, and a key flies off the counter and hits them on the head. It is a day of about 80 degrees, but the key is ice cold, as if it was in the refrigerator. The house does not even have air conditioning. Is this just someone's mind playing tricks on them?
Is this an actual scenario you personally have experienced, or is it hearsay? This story sounds like about a thousand other ghost stories we tell around campfires... probably nowhere near an accurate retelling if it is third party.
That being as it may, just because an occurrence does not have an immediately obvious explanation does not automatically have to become the work of some mysterious entity or other. Can't you see this?