I don't have nightmares very often, maybe once a year at most. I do have anxiety dreams so there is fear occasionally but not terror. However, I don't recall ever dreaming about blood and if I have violent dreams, they're even less often than nightmares. Being chased and running; I use to have dreams like that but don't usually anymore, since finishing therapy. I've never had a flying dream though I understand they are supposed to be pretty common.

I think symbols are kind of related to the individual; in other words, I have had a lot of water and stair dreams but the next person might only have occasional ones, I use to dream about animals and snakes but then insects were more common and now I don't dream about those very often either, etc.

It could be your psychiatrist is just asking for his own theories (has had people with X problem who dream about blood/violence respond well to Y med) or he could known something about certain dreams being related to certain neurological outcomes (as my earlier post showed) or could have just wanted to know what kind of dreams you dream/start an easy conversation with you.