sleep paralysis while still awake?

In the last week or so I have been noticing something odd when I am trying to get to sleep.

Just as I am laying in bed trying to get to sleep I get a weird feeling build up in my stomach, feels kind of like indigestion. This gets worse then it peaks with a bizarre sensation, like a flash in my mind and I cant move or speak. I can hear my girlfriend in the bed next to me either snoring or sometimes reading but I cant move anything but my eye lids. I lay there with my eyes open and cant do anything.

Its lasts only for a minute then is gone. I notice this anywhere from 1 to 3 times a night and its been every night in the last 10 days. Before that I have never experienced it before.

I have been diagnosed with a cranial fossa arachnoid cyst about 10 years ago and am on morphine medication for a spinal injury and from that have never been a good sleeper. I average 4-6 hours a night but it is always very light sleep and wake easily.

What can I do?