Trust me, we've all been there, it won't last.I only have about 9k likes and I get about 2k reach. Just like Google, Facebook uses an Algorithm to display your posts to your fans. The more interaction you get, the more reach you get. For a post with an image I get about 50-70 comments and 40-50 likes and it gets a 2k reach. For ones with a link, you can half that, but even still it's OK.