Retesting for covid is not useful as it can show positive results even after a person has recovered from covid due to the presence of dead virus particles in body secretions, so rt-pcr isn't a test of active infection. Your d-dimer score is in the moderate risk category, but d-dimer scores are only significant if they are repeated and show an increasing trend. The same goes for crp. So if you don't have any symptoms like fever, sore throat, dry cough, breathlessness or diarrhoea; there is no reason to be concerned. There are however post-covid effects often seen which can present in a variety of ways, so if you are facing any difficulties, you take up an online private consult with me and get a suitable treatment plan to manage your symptoms.