I've just caught up on this thread. I'm really glad you've found all the advice you received on this thread helpful. & that it exceeded your expectations. Thank you @xXLexi_Lou122Xx@Tiny_leaf and @WheresMySquishy for providing @happyisgood with such great support. You all should be very proud of yourselves.
Dealing with strict or idealistic parents (if that's how your parents are) can be really hard. If you've tried your best, then you should feel proud of yourself, no matter what mark you get. Also, if you find you need help in certain areas, then seek the support you need - there is no shame in that. Is there any subject in particular that you're stressed about?
You asked for some recommendations on how to manage stress so I have linked some good articles/videos for you:
I personally find breathing exercise helpful for stress. The app "Calm" has heaps of good mindfulness/meditations sessions that might be worth checking out.
Also I read that you were discussing potentially seeing a psychologist. If you're unsure of how to go about this, then these (here and here) articles may be of help to you. If arranging to see a psychologist at this stage is too difficult, does your school have a school counselor that you can chat to?