If these are very vivid it could be a sign of some sort of psychosis, actually sounds like some of the symptoms of schizophrenia, which you can get medication for.
Also, I don't know anything about your history, but I know that acid users can have vivid flashbacks for the rest of your life, so if you've ever used acid or another potent halucinogen, this could be backlash from that.
All in all though, it seems like you're actually maintaining yourself quite well mentally. The fact that you're very aware of the nature of these "visions" means that you understand they are not a divine message, but instead are a fixture of the workings of your brain, and it means that you are less likely to become violent or dangerous as a result of the visions. A doctor would help a lot of course, but since we don't care enough to give people free healthcare here in the U.S. it's quite understandable that you find yourself out of luck. Just always keep in mind that the visions aren't real, and you should be fine, even if you find yourself emotionally jarred by them at times.