Try to figure out why you are in such a hurry. For example: waiting for an important party to start! We tend to lose our patience when we're multitasking or when we're on a tight schedule, expecting the day to pass within only a few short minutes of busyness and chaos.
If you're stretching yourself too thin, you should reconsider your to-do list before you attempt to change your natural reaction to an overwhelming situation.
Try to spread out your tasks so that you're doing only one thing at a time, without leaving yourself twiddling your thumbs in eagerness of something to busy yourself with.
Delegate responsibilities to others if you can; this in itself may be a test of your patience, but you have to learn to share the load.