breath, calm down, and be logical for one moment. while Ouija Boards can and do make contact with all kinds of spiritual beings, it could be all in your head. first, were you with anyone else, they could of been moving it [try to find Jim Carry's joke about using a Ouija Board, quite funny imo] if you were alone at it started moving, you could of been. i forget what it's called but basically your muscles are always moving, that coupled with your subconscious can explain why it's moving. be sure you're not holding on tight, your fingers should be barely touching the planchette.
did it just started moving back and forth without you touching it? doubtful unless it's an extremely powerful entity. the reason one must be touching the planchette [pointer] is because spirits need to channel through the person using their [person] energy to move it since most spirits are not that strong.
third, how did you make it? did you cleanse as well as charge it? did you cast a circle? did you purify the room after using it? [sea salt or sage smudge works] these are some things you should do. if you're afraid something evils coming to get you, cleanse the board, and the room you used it in. if you want to be extra careful, cleanse your whole house. wash your floors and furniture with a cleansing brew [sea salt, rosemary and lemon juice works] and place sea salt on every windowsill. be sure while cleansing all your windows are open and you say a chant, or think, 'get out' or something to that effect.
before using the board again, be sure to research and do things correctly next time to be safe. if you're still worried about the Ouija Board, please, whatever you do, don't destroy it, that's a really bad idea. look into a safe way to do so, instead of just chucking it onto a fire or something.