Spirit Guide Or Ghost?

I want to add before starting the story that I'm a medium, have a strong sense of ESP and precognition, and an empath.

Two weeks ago, I rode the bus to school and when I got there, I felt someone or something with me. I kept on going through the day as normally as I could, but it was bugging me.

All the sudden I see a white orb go through the classroom door and disappear. Half a minute later, I see it right in front of me (between me and my friend and my teacher). It goes right in front of my face and it disappears. I feel unbelievably cold and after that I couldn't focus because of how warm it got afterwards.

An hour later, I feel completely normal, but I could randomly see white outlines of people (I think they call it auras, am I right?). But after a bit, all the auras disappear. I wanted to see them and they showed up to me again. I felt totally freaked out about I continued on with my day.

On the weekend (8 days later, 2 days ago), I heard my name being called from the living room. I was in the kitchen and I spun around on the chair to see if my mom called my name. She was asleep on the couch and my brother was sleeping on the floor. Not even the radio or TV was on. Then, I look up and see that white orb again.

I heard that everyone has a spirit guide so I started to meditate more and more. One night, I was dreaming and I saw a shadow, just a shadow, with the same feminine voice I heard during the day from the living room.

Could this be a ghost or a spirit guide? Why would I suddenly see auras after seeing that white orb?

Thanks for taking your time to read this and help out someone!