oh gosh, Vaheguru
I'd be 22 soon, at the fact of marriage just scares me still. I mean your only 15. I would say you need to actually speak out the truth to your parents, I know you respect your parents but in some cases you do need to tell your parents whats right and what is actually wrong. And dont worry, you know guru ji is on your side, if you dont think you are ready for the marriage then say it straight.
Ask your parents whether they love you? And if they want to see you happy? I'm sure that a childs hapiness means alot to a parent. Just that once ask your parents to make them realise, if you love me and want to see my happy then the only way is that I want to study get a career get an education, then decide on engagement and marriage.
As for the society who cares ??? as mentioned before by sarpanchni_007
I agree with that totally, you need to impress guru ji not the society. It's your life ahead, not the societys, its you who will be marrying not the society. so called society just has a habit of doing Chuglya, then thats their own problem, guru ji will sort them out.
Penji make your parents aware NOW & Good Luck :TH: remember one thing Guru Ji Are on your side, so no worries
Hope you sort this situation out
Vaheguru