Is it happening when you are awake or asleep? or after sleeping? I had very similar dreams all the time when Em was little. I would wake & think I dropped her from the bed only to remember that she was in her cot. Or that DH was rolling onto her etc. I think that's just our subconsious being overprotective of our little ones.

If you are wide awake & it's happening though, I'd be seeing someone straight away. The fact that you were able to snap yourself out of this last one tells me that it's not PNP, but if you are unable to see that it's not reality, do seek help ASAP.