My therapist taught me that this simple breathing technique shifts your brain from the sympathetic (anxiety located, fight or flight) system to the para sympathetic nervous system (in charge of slowing heart rate, relaxing digestion etc.)

You simply inhale shorter than you exhale (count three during inhale, eg. and count five during exhale.) The shift happens automatically and immediately. You don’t need to meditate for five hours! Amazingly effective for me when I get anxious.

Masturbation is another good idea though.