I understand your concern with your health issues. Coming to your throat, seems like you had a severe infection of your tonsils, which has not yet resolved. You probably need a throat swab to see which bacteria is growing, and treat the infection accordingly.
Soreness on tongue could be related to the infection/ medications. Use hexidine mouthwashes to reduce the burning sensation. The bump on the thigh seems unrelated to the throat infection
. It could be an allergic reaction
, as you have rightly suspected. Hope this answers all your queries.
Hope you recover soon,
Dr Vaishali Mehta