Idk if this will make you feel better but since GCSE I probably revised less than 5 hours, completed sociology, history, politics and EPQ for Alevels, got into a decent London uni and graduated with a first in History! Anything is possible. You should still revise as much as you can! Just recollect your mind and don't panic. Remember these results don't define your future so don't go stressing over it and causing your health to deteriorate.