From time to time I have strange feelings when I wake up. I hear the whirring of a fan and other sounds but I am unable to move, as if I am paralyzed, and I cannot open my eyes. Strange sounds mingle and I feel as if I am hanging in a place that I do not know. I scream but my voice is not audible. It has happened many times, which means these things are not dreams.
My question is, is it possible that such things occur out of Jinn possession or from envy or the like?

All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

These are Satanic vexations that are prompted by Allaah because of non-observance of Prophetic supplications.

Here is the cure:

1- First and foremost, observe the prescribed prayers at their due times.

2- Perform the voluntary prayers both before or after the prescribed ones.

3- Make many other voluntary acts of worship.

4- Remember Allaah and mention Him in all situations, like making morning and evening Athkaar, supplications before and after sleeping, and after ablutions.

5- Recitate daily Chapter Al-Baqarah until these Satanic vexations are over. It is permissible to read it two or three times if you have further experiences. 

Allaah Knows best.