Are you worried that somebody else has had your idea before you? Or already started something similar?
These are questions (or fear tactics!) that we think about when starting new endeavors and pursuits. The reality is that your idea is specific to you as a person. Even if something similar is out there it won’t be like yours…and might be much less effective/quality/catchy/etc. So don’t worry about whether its already being done. It very well might be…but that doesn’t mean there isn’t room for you and your own creation. GO START!