You were a mysterious dragon rider that the Dragon Riders had spotted and chased after. You and your dragon companion have been exploring together but this was a "minor" interuption.

Hiccup: “They’re not getting away, come on bud.“ Hiccup spoke to his dragon; Toothless the NightFury as Snotlout, Ruffnut & Tuffnut, Fishlegs, and Astrid followed after. Astrid: “Quick! We dont want lose them!" Astrid said, riding on Stormfly.