Explosive head syndrome

[Wisteria]

Hey I thought I would like to ask a medium for advice on this, Has anyone experienced explosive head syndrome? I have recently been suffering with this it is like a sudden loud explosion when I am about to drift if to sleep, or I hear a loud knocking on a door but no one else hears it only me, enough to startle me, I have jumped out of bed searching where it came from but nothing, I have no history of mental health, I was scared at first, but I am not anymore, I am able to allow it to come and go being able to re settle, but I am wondering if it is connected to my self discovery through my spiritual awakening? I have been trying to find myself and connecting inwards, I had some strange experiences as a child, It only happens as I am about to drift of to sleep, sometimes I feel there’s a presence in the room, but there has been no one there physically, I just don’t know why it happens, is this normal?