is it too late?

4 weeks till exams and i haven't started revising properly, i am planning to revise now but what really annoys me and really stresses me out is the number of people that are revising 10+ hrs a day everyday, making me feel extremely stupid. Also everyone around me keeps telling me that i'm starting way to late and i shouldn't even bother now but i don't understand why? in my mock exams i started revising 2 weeks prior and the day before each exam, i got one of the best in the yr group (arguably even the highest but i don't wanna sound narcissistic) including 9's, is it really that late?