Extremely Sore Throat, Red Blotchiness In Soft Palate, Blisters In Throat. History Of Tonsilectomy, Smoker. No Help From Amoxicillin. Advice

I've had an extremely sore throat for over two weeks now. Last week I went to a clinic because it wasn't going away. The only thing he said was that he didn't think it was strep (didn't do a test) and gave me amoxicillin. I've been on that for 8 days now, and still no improvement. My soft palate has some slight red blotchiness to it, and there appears to now be a blister/sore on the lower right hand side of my throat. No tonsils as those were removed ages ago. I have no other symptoms such as fever or cough. I have extreme fatigue however, and I am a smoker. I have a picture of my throat as well if that will help. Any advice would be greatly appreciated. This is causing me some stress! Thank you!