My grades are not worth anything?

I feel really really irritated and frustrated. There actually seems to be no reason at all for me to feel this way. But that is the case. I got my final prelim results today. I got a C5 for General Paper. 3 distinctions and 1 D grade for Physics. Personally, i'm very happy and proud of myself to have achieved 3 distinctions. But i'm very disappointed about my Physics grade. And i know the full reason why i have gotten a bad grade for Physics. But my parents were not happy at all. I feel pressurized by my parents. They asked whether i could get into engineering or medicine course with the grades i got. Now, why would i want to do engineer or medicine? They clearly know that i no more have any interest in those two courses and i've always been focused on some other degree course in Biomedical Sciences. And yet they ask me this question.

When I said that i couldn't because of my physics grade, they said that the 3 distinctions have no value then. That i shouldn't even have gotten that grade. Such narrow-mindedness! They could have atleast scolded me a little and then encouraged me a bit. I would not feel so depressed. They are not being of any help to me when in comes to physics. I should have dropped it last year itself. They treat the prelim results as if this is the final grade that i'm going to use for my university entry. I can understand their wishes and unrealistic expectations. But just because they want me to achieve something like that, it doesn't mean that i should right? I study for myself, for my sake, to satisfy my wishes. Not others'. And i'm sure i'll do better for my actual A'levels.

Anyway, this is the reason why many students today face problems and stress because of parental pressure. I don't know why parents should be so rigid. Most have a view that good exam results equal success in life. And they don't realise that exam results are not important, but it is the way the results are used that gives the students the happiness and satisfaction. A person might get good results, and get into engineering. But it doesn't guarantee his happiness. His happiness and success depends on how he utilises his time spent in that course and his interest in that course. Parents should realise this. They should not impose their ambitions and beliefs into their children. They should be flexible in allowing their children to pursue their interests. Why should it always be engineering or doctor or some other professional course, i simply don't understand.