I think I heard a ghost

Yo so this is really weird right. I was in my student shared house all alone the one day. Out of the blue I heard what sounded like this old little man say "hello?" Sounding all confused. I thought the sound came from the front door. I went to go check it out worried it was some old lost man. There wasn't a person in sight. So I was a little confused and felt concerned.

Anyway 2 days later my mother contacted me. She said that she just found out that one of her uncles who was in his 70s had died of cancer. He died on the exact day I heard that voice. Now sure this could be a coincidence but I wonder if I actually was visited by him after death. I never met him but what if there's a reason he came to me...