Always in my mind.

This sounds remarkably similar to what my own anxiety does. I cannot tell you the number of times I thought I was dying because of an unidentified pain, only to realize at some later time that it was just my anxiety or some other emotional problem.

I have anger issues and I agree that my daydreaming can definitely make them worse. Have you tried to look at the root cause of your anger, or maybe even more importantly, the cause of your daydreaming? A lot of people, myself included, use daydreaming as a coping method for life problems like anxiety or dissatisfaction with who you are as a person. Sometimes if you can address that root cause, your urge to daydream will ease a bit.

I would recommend mindfulness to teach yourself to stay in the present moment, even if its unpleasant, but in some cases mindfulness can make things worse. If you're in a crisis of any kind, I don't really recommend it. Maybe if you were already trained in mindfulness it wouldn't be as bad, but starting out can bring up a lot of unpleasant emotions and feelings and when you're in crisis that really isn't a good thing. I know that from personal experience.

Maybe progressive muscle relaxation? It's related to mindfulness, but its less about accepting your present experience and more about releasing tension in your body. Perhaps that might help ease some of your pain.

i'm an Over Thinker. I see a trivial event and make it into more than what it is. Then there's the MADD. Overthinking causes a LOT of anxiety, and there are times the overthinking gets to be a bit too much, and i wind up just trying to find something more positive to focus on. Enter the MADD..

I think the MADD to me was brought on when i was seeing a psychologist many years ago, who didn't realize the magnitude of trauma i experienced growing up. Whenever i would start talking about my childhood, she would basically start that "Think happy thoughts" or "Keep it Positive" "Stop bringing up the past" "Get over it" dialogue. She made it seem as if talking about trauma, abuse, sexual abuse was "taboo"..  If i talked about being backstabbed or bullied - which happens a lot when you're a minority, she would basically say i was being paranoid.  She knew nothing about other cultures, nor did she even wish to learn.

I thought that "spacing out" or "dreaming i was in a much more peaceful place" " happy thoughts" was what i was supposed to do.. anything but dealing with traumas/betrayals that shaped me as an adult.

Now i realize, i was doing more harm than good.. :(