Try to stay clam, I know this seems very very bad; however it will be okay; after all the sand is not poison and toxic, this same thing can happen in the wild with hurricanes and storms.
Just let the water clear up and break out the turkey baster to gently start cleaning the large sand granules out of your corals and rock work..... start from the top and work your way gently down :-)
Good luck with your project, and hope you are feeling better soon mate
