That happened to you too! I thought I was the only one! Before it would be me just trying to hit a vein and someone was about to come in the room and catch me...and I would wake up swearing that there was a full rig somewhere around my bed.
But now, The person is in the room and either cuts me with a boxcutter, or I am trying to fight them off but its like my punches are going through water and I can't move....I wake up sheets soaked in sweat after those and my fight or flight response is triggered enough that I keep a .5mg xanax next to my bed because the first time I had the violence in the dream I woke up screaming and just ran out the front door in my undies.
It's weird because this sounds so very similar to the using dreams I have.
In mine, I'll be trying to prepare a shot, and it won't work out (people interrupt me, or I can't seem to prepare it before I have to go do some other inane activity), in other ones I am able to inject successfully and feel effects (very realistic which scares me).
Often people will be chasing me around trying to shoot me with a gun, and for some reason it doesn't seem that bad and I just run around trying to shoot them back too,
Other times I am just "fleeing" others, and trying to avoid others.
It never seems to bother me too much in my dreams what's going on, and then I wake up and I suddenly come to, and the anxiety/panic starts.
Oh and everything you said about you try to punch but it's like you swing in slow-motion, like you're underwater but nothing else and no one else is, that's exactly what I experience too. This is a real-life phenomenon that is present in every-day life during anxiety/panic attacks, and I tend to experience it a lot. I believe this, as well as the shaking, sweating, panic/anxiety is all due to increased blood pressure/heart rate during the dream sequence at night.
Why does this happen? Cardiovascular health could influence this a bit, but it's likely PTSD. Recurrant nightmares which induce panic attacks are very typical for PTSD people like myself.
There are medications which can prevent dreaming altogether and should in turn prevent this effect, like alpha blockers. However, it is best not to use these medications, as your body does indeed become physically dependent on it, and you will have hightened BP/heart rate upon quitting alpha blockers.
