Okay So this dream really stood out to me ...
I was at the doctor's office (paying a bill I think) and When I turned around to leave I saw my Ex, my son's father (We'll call him Joe). I got back in the end of the line to see if I could catch a better glimpse of him. As I got closer to him and looked directly into his face, his face changed in an old man's face. I turned and walk away ... Only to see "Joe" again heading out the door to his car (a tan towncar) This time I seen his face directly and it was Joe! Then I snapped out of it and realized I was "daydreaming" while standing in line at the doctor's office. I seen all this as if it were really happening in my dream, but it wasn't. It's kind of very confusing to me. And I got the distinct feeling the "Joe" was in some sort of trouble...

Does anyone know what this could mean?

Potential One: Perhaps it is precognitive. That you are at a hospital and that you have a feeling Joe is in trouble may be an allusion to his suffering health problems. That he has aged shows a deterioration of the physical body in some form. It might not be serious, however, since he is leaving the hospital and proceeding to potentially drive away.

Potential Two: Perhaps it is subjective of your mind state. Maybe you worry that he will leave you in a sense, that time is marching on and people tend to leave each other by ill health or happenstance. Driving away, leaving you to care for your daughter alone may be a concern of yours that symbolically manifested itself in your dream state.

You may be worried about how he will fare for the rest of his life? Do you feel guilt about him?

What were the circumstances of your breaking up?

Paying a bill at the doctor's office could have to do with the idea that you feel guilty about something and you owe something - that you are responsible
for fixing something.

Joe looking old could have to do with the experience he has been through "ageing" him - maybe making him more wise, more suspicious of people, etc. How do you think he has been coping with things?

Your feeling that he is in trouble could be based on something that you are noticing unconsciously in waking life.

Do you keep in touch with him? Are you and he still on good terms?