Here is an exercise for you to try.
Pick a day when you can spend the entire day writing. I know, it is hard to do, but just plan for it, put it on the calendar. Make plans to be totally off the grid, and to leave your telephones off.
Go to five different locations and try to write for an hour in each. At least spend an hour in each place with the intent of writing. What types of places should you pick? Well, libraries, colleges, cafes, diners, the woods, the beach, your car outside Taco bell, in the lobby of an office building, in a stairwell, wherever. Do script out your day the day before so you do not have to think about anything other than writing.
The following day, and then a few days later, do some journaling or talk to a writing buddy or mentor about what you learned from the experience. Here are these three question to stimulate your processing of the experience.
1) What did I learn about my own process of writing?
2) What surprised me about the experience?
3) What can I incorporate into my life to make me more productive?