i was playing football & me & another player jumped to header the ball. he raised his elbow & smacked it into my cheekbone. i fell onto my back & winded myself. when i opened my eyes i was blind for about 5 minutes & one of my pupils would not dilate for about 1/2 an hour. the medic at the sports centre said i had concussion. i am still feeling dizzy but my eyesight is fine - the area around my cheekbone has swollen. should i go to casulty or just make an appointment to see my GP on Monday?