There is no mention of A levels in your post? Although not actually necessary, it might well indicate that you have sufficent grey matter to succeed ? Three Bs or better would be ideal.
Although the level of Maths for the exams is at GCSE level, you need to feel comfortable with numbers. Physics is also an important ingredient.
The ATOs will ask you to complete aptitude testing etc, to ensure that you have sufficient ability to commence the course. You need to do more than just scrape through. Only a good result is acceptable, as you do not want to be classified as a TRAINING RISK
The course does require dedication and a good work ethic.
Has this been demonstrated in the past?