Baby movement

I'm 18+5 and today felt my baby move (for sure) for the first time. It was the most incredible thing. I was sitting next watching a show with my husband pretty late at night and felt it. Follows by a series of flip flops! How do I go from feeling nothing, to obvious flip flops!! It's like the babe just woke up!  It is the most incredible feeling I've ever had. I can't wait for more to come!!