Getting the abs to show is DIET control and plan of attack plan--FIRST.
Then when (and if, genetics willing) one gets the abs to show, it is also difficult to MAINTAIN (I believe it can be just as hard or simular as compared to the road to get them to show). Though one has to have a DIET PLAN for the Abs, once there, one has to have a MAINTAIN PLAN (if this is long term goal)
Personally, I wouldnt be too concerned (or overly concerned with BF%). True, one has to drop body fat low enough to see the abs. However, with proper DIET and "complimenting" this DIET with appropriate "overall" bodily exercise, you will lower your body fat, and let yourself be the critical judge. (You could drop another 1% bf and still not see them (possibly), this is why I say dont be overly concerned with BF, unless you want to track this).
If you can FEEL THEM, this slightly indicates to me that the abs sheet already has abs squares already there (if you will), and the genetics are possibly there already in place.
The small portion of fat must be removed to clearly see them, however. And as this is removed, ab torso definition will surface itself to you according to your genetic composition and DIET control.
You will get some GOOD OPINIONS ON THIS, however, you need to give more detailed information about yourself for others to help.
for example, your age (17, we have), weight (I have no idea what stone is, lol),and height, as these are important factors in giving the advice you are seeking. Like learning your caloric MT (maintenance Line, and working with this on a higher or lower level) and tayloring a program circumference around this. In addition, is getting the abs to show, ALL you seek?
Now remember something young man: I dont know your knowledge of diet and exercise, but I feel the need to tell you, that you do NOT get abs by bombarding the abs with exercises thinking this will make them show, nor can you spot reduce. Some persons with proper genetics have gotten abs with no cardio or ab exercises. Some dont work them at all (as one can get indirect torso/ab work done through other indirect exercises, example, Squats). Arm yourself with knowledge about the GOAL YOU DESIRE--IT WILL REWARD YOU 10 times more than the time you put in it, I promise.
Get your DIET straight, EAT CLEAN, couple this with a training program. ASK QUESTIONS and give information, and you will get it.
As for me, my body responds WELL with cardio (and yes I HATE IT, but I DO IT, and thats that BAH! to my dislike, I am just more stubborn than the dislike for cardio--mental thingy), and I get good response through just deficit dieting coupled with squats, deadlifts, BACK, and lastly ab work.
I bring this up for a point: You have to find out what works for you, but I believe in the begining we can assume some fundelmental (for sake of arguement) basics to get you started.
YOUR HEAD IS YOUR LEADER: its like screwing in a light bulb: Twist your mind INTO YOUR GOAL, and IT WILL LIGHT THE HELL UP! (LOL, just dont let it POP!)
DONT BE ASHAMED OF YOURSELF! There will be no one on this forum, worth their weight in gold, that is going to attack you for displaying your STARTING POINT pics, etc. THIS IS WHAT ITS ABOUT! ROCK ON, BE HARD, BE MOTIVATED, LOOK AT YOUR GOAL, SEE YOUR GOAL, and walk up to it and SMILE, and snicker at the same time, and rip its face off! And, my tradional statement: if you fall 5 times, get up 6 times, the trick is getting back up: As staying down is just that, your gonna stay down and get no where, but getting back up, gives you another chance to head butt its @ss. GO BRA!
Seek and you shall find: There are many paths one can take in a journey and many forks in the road. But, when you properly educate yourself in the goal you seek, this will allow you to learn which fork to take and lead you to your goal.
As you get advice, remember this: There are no bad bodily feedbacks in my opinion whether its negative or positive. The negative portion may not be the one you wanted, but its feedback and SHOULD TELL YOU SOMETHING, and how you handle this can determine alot of different things on your journey toward you goal.
Off topic: By the way, LOL, you have the typical messy bed room, if this is yours in the background of your photo (LOL).