I've had some of my stuff pinned as well. I take it as a compliment. I really don't care. Most everything I make is a take off traditional patterns anyway. Or, I bought the magazine or pattern to make. I get a lot of inspiration from Pinterest. I like to look and make the boards for future ideas. Sometimes, I am even inspired to make something from them. But, I don't sell or "quilt" show what I make. I gift or make for myself marking the item with the inspired persons name as designer.
You can watermark your photos if you want to with your name. There are tutorials online to show you how to do this.