Your story isn't weird. You're a kid, and kids are supposed to think like children. It's kind of completely normal.
Look up the history of the Ouija board, the real history, and you'll see it lose its magic really quickly. Notice how it was invented (not discovered in some ancient tomb) as a toy, sold as a toy and used as a toy, and how it was completely harmless for decades. It wasn't until a self-proclaimed psychic wrote a book about using it to talk to dead people before the Christian church went all nuts. Nobody had ever heard of a Ouija causing demonic possession until The Exorcist became a hit in the 1970s. Could that really be just coincidence? Really?
Think for a minute. A cell phone that only contacts the living costs hundreds of dollars per year minimum. Would a device that can contact the dead, with unlimited text time, really only cost fifteen bucks? At a toy store?
Doesn't add up, does it?