jimlad4,
From an old codger - GO FOR IT. I did OASC in the early 60's with a few O levels (GCSE's to you) and 3 years as an ATC Cadet. I ended up flying all over the world.
If you don't get in the first time then you can try again. If you don't try then you will never forgive yourself.
BEST OF LUCK!!