I like that idea. If our minds didn’t wander, how would we come up with new ideas and ways to solve problems? I doubt that we could allow our minds to wander without being subject to at least some unsettling prospects popping up.
To the OP, yes, I get those thoughts. They do a timeshare in my brain with the thoughts of “what if X horrible thing happened”, where X is out of my control. I guess you could say I’m prepared for a number of eventualities. 
I have that one every time I drive over Sancho el Fuerte Bridge. This post is not being written by my ghost… I think!
Also, if I think of horrible things, they can’t happen, because that would be like precognition, and I don’t believe in that.
I don’t think I do, or at least I am not aware of having them. I had such thoughts for a short time and I went to a doctor about it because it was new and unpleasant. However, when I talked to my husband about it he told me he had thoughts like that every single day and did not quite get why I would want to see a doctor.
But I am not normally a visual kind of person, I don’t have visual thoughts in general exactly. So their sudden and intrusive appearance was a bit of a surprise.
I think you should first, as soon as is convenient, seek the advice of a medical professional in your area who can talk to you at length about your situation.
Closing thread.