I twitch and jerk a lot in my sleep since my deployment. is this a form of ptsd or sleeping disorder ?

Maybe: Thank you for your service. The stress of deployment can last for months. Some recent studies by the military show that the body doesn't return to normal for up to 18 months after returning from combat. So twitching and jerking is probably okay, as long as it doesn't affect sleep or daily routine. If you have nightmares you should see a doctor as there are effective treatments for this.

Sign of stress: Stress tends to give restless sleep as you don't seem to have other ptsd symptoms. Work on relaxation and try other ways to work on issues bothering. Individual and group psychotherapy will help.

Adaptive behavior: Thank you for your service to our country. Remember that being able to wake at a seconds notice helps to keep a soldier or marine alive in combat. It is highly adaptive. It may take a number of months in conus for this to diminish. If you find that as the next six months role on that you are hypervigilant, avoidant of people, places & things due to deployment & reliving often- then seek help.