I doubt that. It is not a very hard pattern to think of, and considering how many ZUN already used, it was inevitable. For example, Shou's first card, Radiant Treasure (Gun), is extremely similar to the third card of my Sariel script. However, the chance that ZUN has "stolen" from me is practically below Zero. :V It is just a pattern that anyone who spends enough time with developing bullet patterns will come up with sooner or later.
Then, of course, you have this nice little thing called cryptomnesia, where you subconsciously use something you've seen somewhere else without yourself remembering that you did, causing you to assume that it was your idea all along.