Lol, My advice is different.
Well, it actually depends on the university you are applying to. If you think that by concentrating on your A2(s) you will achieve the grades required than no need to re-sit but if its, for example, a country like UK then you should re-sit.
Your results are good mashallah, if you decide to repeat then i will suggest you to re-sit only physic unit 1 as your chem unit 1 could have been B by only 1 mark and you can catch up with it in A2.
Best of luck