Trouble with getting into aviation
Gliding is not the only course available.
As a former CI, I can tell you that there are many scholarships available if you look hard enough.
You are too young for the gliding scholarship anyway, don't apply for that until you are approaching your 16th birthday or you'll just be annoying your adminO.
Don't rubbish the air experience flights. That is an extra free half-hour of tuition that counts towards the total as long as you log it right. Ask to do a session if circuits or general navigation instead of aerobatics next time.
Opportunities are there. I spent long weekends pushing Tiger Moths around at a vintage airfield, that got me some (vastly) reduced-price lessons too.
And don't belittle those minimum wage jobs. I took up supermarket stacking alongside my A-levels. Cheaper groceries, some work experience, a payslip every month, and some new friends. Just saying.