[Gen 7] Got 2 shiny yesterday

Just start shiny hunt both Johto legendaries yesterday and after under 200 reset I assume, Lugia is the first one to shine and managed to capture it in Beast ball.Then,I continue to look another wormhole and got Thundurus.While setting rubber band,I suddenly heard shiny sound and to be truth,not really expected to get shiny Thundurus at 1st encounter.