Performed oral sex on a girl on Saturday last. On Tuesday I developed flu like symptoms (high temp, aches and pains, headache) as well as a bad sure throat which has got progressively worse even though I have been taking ibuprofen. Is it possible it could be an sti or is it likely to be merely strep throat?
You have not mentioned if the girl was a sex worker for infections from sex workers can be very resistant, anyway private parts of females are loaded with various opportunistic pathogens, which an entry to oral cavity can cause infections of various kinds.  You are advised to get a throat swab culture and sensitivity test done at a reliable pathology lab, and take appropriate antibiotics and supportive treatment (Betadine gargles, b-complex, analgesics etc. for full recommended duration. Ensure hygiene of your partner before indulging in abnormal sex.