Sometimes I feel.... very comfortable, relaxed and concentrated at the same time. Nothing can distract me.
And sometimes I feel very nervous, everything distracts me - lights, sounds, people looking at me, etc. When I'm outside, I feel need to walk faster and faster. When indoors, I need to do something all the time, but can't concentrate on anything for a long time. I'm switching pages in the internet every few seconds, checking for new postings again and again, etc. Fortunately, this happens not very often. Usually when I'm tired too much.
So... why this happens?