A week ago, i was playing basketball. then someone's head hit my head, i fell to the floor for about a minute. my right eye was blurry, and i couldn't?

Be seen: Your question cut out, but if you are saying you have had blurry vision after a collision playing basketball, and it is still blurry, I would be seen immediately. Would be worrisome for ocular problems such as a detached retina, or cranial conditions such as a post concussive syndrome.

Finish sentence?: It's important to know what it was that you "couldn't". It sounds like you had a mild concussion, but you've passed the period during which a more serious injury would show up. If you had temporary vision loss in 1 eye, it would likely be from a direct blow to the eye area or concussive force to the vision center of the brain. If you are still having symptoms, please get medical care.

Trauma: Are you still having symptoms? You need an evaluation with a physician asap. You may need imaging study to make sure there are no intracranial abnormalities.