Was throwing up w/ stomach flu, broke a blood vessel in eye, now 3 days later I have a small blind/blank spot in peripheral vision of that eye? Thnx

Unrelated. Sounds like the broken vessel in the eye an the blak spot in the peripheral vision are not related. The latter might be related to the "stomach flu". Need to see eye doctor and check visual field and other work up.
See an ophthalmologi. Go and see an eye doctor now. Your eye and its capacity to see are at stake. You may have a small retinal separation and if that is the case you will require immediate surgery. Go see somebody in an emergency.