Not good enough,

Feeling quite rubbish today, My mum and dad were in the room nearby and they were talking quite loudly, I stood outside the door and listened in, They were basically saying how low their expectations are of me, How im not going to get into the college I want to go to by the look of my estimated grades which are mainly b’s, 2 a’s and about 2 c’s. Which are all passes, and I was really happy with (as teachers say we will probs go up by a grade in actual exams), I really want to make something of myself, and go to uni, which I heard them say I wont get into uni. I thought they had higher expectations of me, I new they wernt as proud of me as they are my sister whos 18, really smart and going to uni soon after her gap year. I hate being this younger dissapointment. I try as hard as I can, and I feel so low right now. I have an exam on wednesday which I’ve spent time revising on, im not naturally smart but I try my best, now I feel like im not good enough and struggeling to even bother anymore. Should I talk to them? Or leave it, I dont know what to do with anything, all I think about it how rubbish my future could be. Help, x