Whether you should retake them depends on whether you want to apply to Oxford, basically. Cambridge don't accept resits I believe so there would be no point if you want Cambridge. If you don't, don't bother, as those are still amazing grades, and you should focus instead on a levels which are more important and really hard! I know exactly what you're going through, though, if it helps- I got my a level results in August, wanted A*s and As like you, but got Bs and Cs, literally still not over it! You just have to take as long as you need to process the disappointment and then try and put it behind you, not think about it, and you can make yourself feel a lot better by concentrating on your plans for getting amazing a level grades instead! And remember, as someone said to me when I was upset about my grades, it's not the people who get straight A*s who go out and become famous or successful or happy or rich, it's the people who work the hardest and want it the most. sometimes those are the same people, but they don't have to be!