My aura before migraine was different today, white flash with immediate large section of vision blurred with zig zags, not gradual like usual. common?

"Common"?: Not sure what you mean by "common." It doesn't seem to be common for YOU. I recommend you look up "scintillating scotoma" & "fortification spectra" & see whether the descriptions fit your symptoms. Migraines can change over time, especially in women, as migraines are often exquisitely sensitive to either short-term or long-term changes in female hormones.