should I start a book #2 and make it a series?

As a writer, it's sad to finish a book because you've grown "close" to your characters and it's hard to say goodbye. As a reader, you want more when you finish, and I think that works the same for the writer. Do Ali and Bethany have more to their story? I think they do. I'm excited to share more about "Jolt" but I am patiently waiting for the blessing. I can't wait to share!!  Maybe I can share my lead paragraph... that's not wrong, right?