I left school with almost no GCSEs above C (Ds and Es for everything), eventully went back for an extra year to get my maths and English. Then my school kicked me out.
Managed to get into a sixth form college as my school wouldn't accept me for A-Levels. Took a year out to work, then headed to Uni. Managed to stick it out there for 5 years and walked out with a BSc Hons and an MSc. Started flight training 18 months later following a modular route, and even spent a couple of years as a teacher and Uni lecturer. 9 years down the line got into a large Jet operator.
All you need is the patience of a saint and determination. You'll get there eventually.
Good luck.