Abs stretched out due to height increase (Need advice)

[7inchLongass]

I recently grew in my spine. I used to have a six pack. Now that I've grown in my spine I now have these weird looking stretched out abs like how lanky people that don't workout often have. Am I supposed to grow new muscle or am I supposed to have the current muscle I have be stretched out over a larger surface? Any advice or information you can share I'd be very grateful.
(Edit: I'm 18, not 49)

[BS57]

Post pics, otherwise.....