I audibly gasp, even when I am actively looking for a shiny it still hits me with shock, especially if I have been bored for hours or days, encountering pokemon after pokemon that look the same, ready to give up. Then when you suddenly see something different it's almost startling, and takes the brain a moment to process at all.
I usually can't string together words. I'll just barely be able to breathe, and make a sound of disbelief. I am of course excited, but I don't get jubilant like some people do because I know my work isn't over. I'm kinda scared. Even though it's what I wanted, I'm nervous because I have to still catch the pokemon and there is the risk of failing. So I turn very serious and focus to make sure I don't hit the wrong button, and try to stick to my strategy of how I will capture this pokemon. I go slowly.
I think to myself things like which pokeball would be the most useful? I.e Should I use a quick ball since it's the beginning of the battle? A dusk ball because the hunt went on so long that it's now night? A net ball because it's a water Pokemon? I don't care about how a ball looks, I care about not failing.
I also make sure that I am aware of what moves a pokemon knows at it's current level. Is it able for instance to use an attack that will also damage itself like take down? If that's the case I should not use a move like false swipe and bring it's health down to 1. Can it use a move that will kill itself, and if so what move is it? If it's memento then I need to select taunt before I even think of throwing pokeball, unless it's a master ball. If it carries something like self-destruct I switch into a teammate with the damp ability, so it can't blow up in my face.
I also check to make sure that the battery isn't too low so my game doesn't die in the middle of a battle, and I lose the precious Pokemon. If it's in the red zone I scurry as fast as I can to the wall to plug in my device for a charge.
Shiny hunting can be a nerve-racking experience where not concentrating could mean losing the Pokemon you may have spent months hunting for, so my initial feeling of surprise quickly turns to tension. My body will stiffen, I will become silent as I work, time slows down and I may break out in a cold sweat as I carefully try to capture the Pokemon. I can't breathe a sigh of relief until I see that ball shake 3 times, then finally click shut. Then I am allowed to be happy. I smile, cheer, dance around, and reward the Pokemon that helped me. I make sure they are healed up the Pokemon center, and give them some treats and petting. I also go look in on the new shiny, check out it's nature, might think about the Pokemon's nickname some more and SAVE, SAVE, SAVE the game. Did I mention save?