I had oral sex then a week later swollen glands and a sore throat came, i'm 19 yr female what could this be?

Infection: MOst likely bacterial infection but need to rule out STD such as Gonorrhea or chlamydia, herpes and syphilis Were there any visible sores or discharge ?

Maybe strep,flu,etc.: One should be sure to tell the doctor exactly what kind of oral sex is going on. Sore throat symptoms can be from cold viruses, strep throat, allergies, etc... It can be difficult to tell what the cause is. If symptoms only last 1-2 days, it is more likely allergies or irritation. There are rapid 5-minute tests for strep, so a primary care doctor can diagnose strep and start antibiotics.