Hi, welcome to the forum, it can be a manifestation of type of sleep disorder like parasomnias, wherein the certain events occur without the knowledge of the person. There also can be associated grinding of tooth known as bruxism.
Few of the individuals are known to suffer from parasomnias esp. when they are on non-benzodiazepine sedatives, drug abuse etc. otherwise no definitive cause exists in few individuals apart from stress, positive past history of abuse etc.
The associated symptoms with the following disorder are confusional wakefullness, sleep paralysis, nightmares and night terrors. This can occur in any sleep stage (REM and non-REM stage) .
To rule out parasomnias you need to undergo Polysomnyography and sleep analysis. You need to take out time for further evaluation. Sleep with light on. Short term benzodiazepine against prescription will help you. There is nothing to worry about. Go for mind relaxation exercises. I suggest you to consult physician or sleep specialist. Take care and regards.
Hi Dr Rajput,
Thanks very much for your feedback. It's greatly appreciated and I will visit my GP as you've suggested.