Failing Two Classes and Feeling Hopeless

im a junior, and the marking period is about to end. ive had mostly good grades, high level classes all my life. im failing two classes. i just feel so hopeless, like everything ive ever worked towards is coming to an end, that im never going to be able to get into any colleges, and i have no backup plan. my parents have been so understanding, as two doctors recently intervened due to my increased anxiety and newly found depression. they say its okay that im struggling, that i cant help it. but at the same time i feel like i couldve done so much more. i couldve prevented myself from getting so sick and jeopardizing my future.