Another thing that helped me as an IC was keeping notes as a habit. It needs to become ingrained enough that it isn't blocking flow to jot a note into OneNote or Evernote. This allows you to 'see' the interruptions later.
I'm more of a 'pile' based note taker, so it's a gigantic list of timestamps + notes. If you are getting too many interruptions it also provides highly detailed 'proof' to the person in charge.
More recently I realized that getting distracted today is tremendously easier than it was in the past. When I find that is an issue I set a meditation timer to ring a bell every 5 minutes. If I'm not doing what I want to be doing when that bell goes off, I just go back to doing what I planned. At a certain point the bell ringing is just a habit to ensure your attention is in the right place.