While every individual is different, usually in the first 24 hours after a concussion you may experience more physical symptoms, like dizziness, headaches, nausea and sensitivity to light and noise, Bickart said. About three to seven days later, cognitive and emotional symptoms may pop up, such as anxiety, irritability, trouble focusing, memory issues and brain fog.
Article source: https://www.huffingtonpost.co.uk/entry/if-you-hit-your-head-watch-out-for-these-symptoms-even-days-later_uk_69d50077e4b0ae5bb2464a69