How long does it take for a burst blood vessel in back of eye to fix (diagnosed) i have little to no vision in that eye and really struggling?

Seek MD attention!: For a young person (age 33) your description of a "burst vessel" in the back of the eye is very unusual. Possibilities include leakage from a blood vessel such as in diabetic retinopathy or a blocked blood vessel due to cholesterol or hypertension or other source of embolism (clot) such as heart disease or some drugs. Swelling of the macula may present. Best bet is to see a retina specialist.