I think you overtrain your Abs i started exercising when i was 16 i was pretty fat before that,lost many pounds,but i had no ABS,started doing crunches did hundreds everyday for months,But the results where dissapointing.
There is something about doing the same workout everyday,training a same muscle group,they get used to the exercises,accustomed.They dont grow anymore,so i gave up from gaining abs,started parkour,and one day im watching myself in the mirror,what do i see?Abs all of them revealed like a Da Vinci painting.
The thing i want to say is,dont get obssesed with abs,just let it flow,do your workouts,get rest inbetween,do different exercises dont allow your muscles to get accustomed to the workout
Sorry for my english,dont use it much in my daily life.
And im new to this forum so ill use my post to say HI to you all