Lie down, stop everything you're doing, and think about the fear and stress that drives you. Funnily enough, stress, the fear of time passing you by, and poor time management are all linked...
First of all your problems is your inability to savour time.
The key: allow enough time for everything.
It won't be easy at first, because not everyone has the natural ability to live for the moment...but bit by bit you'll find you're less behind, you have more free time and the clock seems less like your worst enemy.
Managing time and mastering time are separate things but they are linked. You can have good organisational skill but a bad relationship with time, and vice-versa. Organising your time allows you to live your life more, whereas your way of living your life can give you a lot of useful pointers as to the changes you need to make. These aren't minor changes, but they will see you make major progress.