My dream patterns are similar to yours and while I forget my dreams frequently, I retain enough to know that I dream nearly every time I sleep, whether it is a nap or a normal night's sleep.

I don't know Fortran so I guess my equivalent is to dream that I am doing simple to complex mathematical calculations in my head. This is my version of a frustration dream since I invariably lose track of the calculation and have to start over. When this happens my only salvation is to wake up, otherwise I am caught in a loop.

When I played computer games excessively a few years ago, a version of this dream was computer keystrokes instead of calculations.

Otherwise, like you my dreams are usually pleasant. They often involve work, either going back to work or as if I had never stopped.

When I was still working occasionally and I was involved with coaching football, I didn't have these dreams so often and retirement was great. Not so much since my back problems ended my coaching and I am fully retired. It kind of sucks. :)

I also have bouts of insomnia and tend to get my nights and days messed up. I often stay awake until the wee hours and sleep late.