I have to agree with TheatreKid here. I've felt/seen/heard people who should not have been where they were. And yes, it's different from a hallucination or delusion, at least for me.

The real question here is how is this affecting you? I can understand the "questioning reality" part of things, but do these experiences otherwise upset you? Are these good interactions with these other people/energies/etc? Or do you feel threatened by them?

If they're not causing you any real distress other than wondering whether or not they are real, then take a step back and just watch them. Listen to what they have to say and see if there is something there you need to hear from them. Do they demand that you interact with them or are they seemingly happy enough to just be there?