Percentage chance of getting rheumatic fever at age 25? had sore throat for one day now i'm worried 3 weeks later

Zero percent: The chance of a person in the US getting rheumatic fever related to a one-day transient sore throat is zero percent (mathematically rounded, of course). Many things are possible in life, but people don't get rheumatic fever from one-day transient sore throats. A sore throat from a streptococcal bacterial infection should last more than one day.