Strangely,  I think I am less disciplined now than before I got published.  Instead of writing,  I am constantly doing research for magazine articles and so on.  So I am making a conscious effort to write at least half a page of prose a day.  And if I don't have an idea in my empty head,  I must keep a journal,  as I once did.  
I hesitate to start the novel based on the screenplay.  I did start two years ago and it did not succeed.  I'd only written a few sample chapters for my agent.  Now I must start again and this is fearsome because I believe that every false start erodes something in you - your belief in yourself and your ability.  (Do I dare write the first word/do I dare eat a peach?)
At the same time,  I do enjoy these features i have to write.  A deadline is a good thing; the spectre of an editor waiting on the story's arrival in his inbox is a good thing. It concentrates my energies.
Writing is difficult.  It is as difficult as designing a bridge,  a poet wrote. 
Yes.