What exactly are you busy doing?
Can you reflect back on the week and detail with any confidence what you achieved? Not just emails, meetings and presentations but proper detail. Unlikely in my experience.
Pretty easy to let days, week, month and even years pass you by without a sense of progress.
Take time each day to document what you actually do. Use your diary to map out each day. Use a naming convention so you can easily search and go as far to colour code each major grouping.
Then after a month of doing so, tally up what you did. You will be surprised as the percentage of each of the categories.
Not happy with what you see, now you have the evidence to do something about it. Structure and plan your output better.
Take control of the time you have.