Ok, you don't need any formal qualifications to be a pilot. None. If you want to go to the airlines or apply for sponsorship that is a different kettle of fish.
Airline flying isn't the only flying you can do.
Let's say it all goes to pieces. Ok, start on plan B. You can redo your exams if you want to or you can skin the cat the other way.
Think about an aircraft mechanic apprenticeship and get into the industry. Work your butt off and study. I have never seen a poor engineer. They always have work. Skills are sought after and make for an excellent back up plan. When it comes to flying, you'll be well ahead of the pack because you'll actually understand the machine.
However, right now, I'd focus on passing your exams and proving your teachers wrong.