Something hacked my macbook and played random music!! Help :(

I was of my house, my sister heard music playin from my room so she thought i was there. (I was in the market). So when i got back home i heard weird music that i do not ven have in my Macbook. I went straight to my room and pressed "Pause". Instead of stopping the song, It played my music. I then stopped it and searched for the music source. everything was closed (Safari, Itunes, Google, Spotify). the music all of the sudden stopped. And i heard some noise of microphone moving 😟. Help