One of the great things about being an academic is how much autonomy you have compared to other jobs.
Autonomy can also be one of the not so great things, too.
If you are working really long hours and feeling overwhelmed with everything you have to do, you might have gone beyond autonomy.
Help is available
Do you know your librarian?
Do you have any funds to hire students or other support?
Are you familiar with your Teaching and Learning Support Centre?
Do you know what your departmental administrators can do for you?
Do you know the name of the IT support person assigned to your department?
Are you familiar with the range of student services available?
Does your university provide a counseling service for employees?
Finding out what support is available to you is the first step in making your workload more manageable.
You will still have a lot to do. But you will have a better sense of the limits of your job description and whose job description includes that stuff you don’t need to be doing.