At the end of the day there is nothing you can do about it at this point, and there is no use panicking until the results come through, and you never know, you might have done better than you think. The situation is completely out of your hands though, so there is no point making yourself ill/stressed/anxious over it.
If medicine is what you have your heart set on, use your anxious energy to formulate a backup plan (whether this is resits, applying to a different degree such as biomed and so on) and make preliminary arrangements, so that if the worst happens and your grades aren't good enough then you aren't going to be stuck doing nothing. Make sure to carefully consider every option because there are plenty of people who this happens to and who would make great doctors but for whatever reason didn't quite get the grades.