Did I just imagine these things?

one night i wasn't alone in my home my mother and my brother wife and my nephew was all with me. I had to get something out of my room and my parents door is right across the hall from my room as I passed the doorway I peered in and saw a man standing on my mom's side of the bed just starring at it, it freaked me out i ran back to the kitchen and told my mom she went looking but the old man was gone. Then a few months ago my brother and his wife heard the bathroom door shut but everyone was in the kitchen, then my mom heard someone sneeze when it was just me and her here and then i heard a man cough but i was the only one here. what does this mean did I just imagine it if so how did everyone else hear the things.