Me? I'm 39........... again.

What is it about turning 40 that scares the crap out of me? I'll be 40 in a few months and it's killing me.  I think about it everyday.  I'm panicking! Why? It's just another birthday, right? I've been trying to find reasons why it's going to be ok....... but I can't. My son is getting ready to graduate from college.  Now THAT makes me feel old. Even though I had him at a young age, I still feel old. Is this a mid-life crisis? I don't feel the need to go out and buy a flashy car or go and have my boobs "done."  I don't have the urge to go find a hot 25 year old to seduce... (no Mrs. Robinson here, thank you.). I do feel like I need to move to another city, as this one is getting boring to me. I live in Nashville, TN. Though it is a beautiful city and offers tons of things to do.... if you're a musician.  I feel as though I've seen it all.  My husband is a musician and I've been to all of the honky tonks, concerts, festivals, etc........ I just want a change.  I moved here twelve years ago.  Not to pursue a music career. Again, for a change of scenery. I had lived in upstate NY for 25 years and moved to Florida with my family after they retired.  We went from extreme cold weather and snow to extreme heat.  It was awful.  Florida was so big and so fast paced that I literally had panic attacks almost daily when I had to use the expressway to get to work.  I enjoy writing and all I can think about is moving to a town like Mayberry, sitting on my porch and writing a best selling novel.  I think about taking a break and going to the beach, or riding my bike into town.  Am I just living in fantasy land? Should I just pack up and leave Nashville to pursue my dreams or attempt to pursue my dreams? Or am I just setting myself up for a big let down.  I just don't know which direction to turn.  I have a job here. I'm not happy with it, but, it's a job.  I just don't want to live my life doing this job because I have to and never stepping outside the box to see what else is out there for me.  I'm almost 40.......  it's time......   right?  Here I go......  panicking.