I am concerned.

I had EMDR... about 10 yrs ago. It was for a water/boat phobia.

If you go too fast, then I suppose things could get dicey.

One of my sessions I had chest constriction, like I was drowning..(it must have been reliving the original trigger).
The therapist stopped it then. I rested about 15min and we started again.

One thing...whatever you are thinking about before the session is what comes up for work. I think you should discuss this with your therapist and do this more slowly. If you think about highly charged stuff, then that is what gets stimulated.

I did get much better with the treatments. But I still cannot bring myself to go under water. But I can now run a boat, and get on a boat that goes over deep water, and not get sick.
I would say that it was good for me, but not a total cure.

There are other eye movements that can be done when you
become...overwrought. Up and Down, will defuse some reaction. That is what happened for me.

I think EMDR is like defragging your computer. Things get moved around. They don't go away...they just lose power to create unwanted physical reactions to negative memories. I never had negative reactions after the sessions. I DID have more vivid dreaming.