I have just be infected with covid. how long will i have high antibodies for this untill i am susceptible for another infection? im not sure what strain i have, but the most severe symptom was a very sore throat,worse ive ever had. and bad cough?

You are young and symptomatic so natural immunity should be present. Omicron BA 5 is the latest and dominant variant so you probably got it. Your antibodies with this variant should last at least 3-6 months but you are still susceptible with a new variant because the mutation of spike protein. However, you will be fine or only having very mild disease with the nucleocapsid antibody & memory cells.