Re: eye floaters!
The 'floaters' and flashes you describe could be attributed to a range of conditions so you really should have them checked by an ophthalmologist (not an optometrist).
The muscle pains and spasms could be due to some other condition not related to the visual disturbances but, just in case they are all connected, you should mention them when you see the ophthalmologist.
Make an appointment as quickly as possible to make sure that this does not develop into something more serious. The Ear and Eye Hospital in Wenatchee would be a good place to start.