Voldemort was roaming by Hagrid's hut!!!?

Hello, my name is Luna Lovegood and I go to Hogwarts school of Witchcraft and Wizardry, for those of you who dont know me. I'm quite good friends with Harry and Hermione, and yesterday I visited Hagrid's hut. I was wearing my... favorite... gles, when I saw a figure wandering around. I then realized in terror it was Voldemort. Harry and Hermione couldnt see him, so I paniced and ran back to my house corridor. They asked me what was wrong, I couldnt answer. They think I'm crazy. What should I tell them?! Help!!