Twitches and spasms ,this is your body sending you a message telling you to cease and desist. Listen to it!
I would never use unbuffered ascorbic acid if I would use it at all, there is some real junk out there passing itself of as vitamin C.
Educate yourself first before doing any protocol ,look into the buffered ascorbates and synthetic vitamin C and the things it is made out of like the waste product high fructose corn syrup!