You love life and all it has to offer you and you're never satisfied, which is why you're always striving to do better and achieve more. Your appetite for life is admirable, but if you carry on as you are you'll end up with indigestion! Try and reduce your appetite a bit and accept that you can't do everything.
The key: Accept that the time at your disposal is exactly the same amount of time that everyone else has too - no more, no less.
Stop and take a look around you. Everyone else is stressed too, but they don't get as worked up about it as you do! Why? Because they're less hungry for success than you are. They accept that not everything they do is going to be perfect and they don't set themselves unattainable targets. Take a leaf out of their book!