All writers have a lot of ideas. Nobody is in the situation where they get only one idea at a time and the second one pops up usefully when you’re done writing the first one. Keep a notebook, write your ideas down. Eventually, however, you’re going to have to commit to one. Here’s a useful article on deciding if your idea is novel-worthy.
“Full measures indeed of love and suffering…and bloodshed too: Fans will sail through and clamor for more.” — Kirkus