I don't know how you do this either, Mamanan. Waitressing can be hard work and the lifting would kill me. I swear they make the plates out of cement. They are so thick and heavy.
I used to be a waitress when in college and I didn't have fibro but was still clumsy! I worked in an Italian restaurant and I had a huge tray of plates to serve. As I was serving one side of the table, I heard a gasp. I looked and the tray was tilted and a plate of spaghetti was sliding off the tray and about ready to land in a customer's lap! I took my free hand and slapped in into someone's dinner. That saved the day and the customers were wonderful. We all had a good laugh.
When you have days like you had, take a deep breath and try to brush it off. I find if I start thinking about it or worrying about it, things just get worse. I do this with fibro fog, too. If I can relax about it and not worry that this is going to happen all day long, it usually settles down.
I hope you have a better time on your next work day. Hats off to you for making this effort, too. I know you are not feeling well at all.
Sherrine