Had Headaches, Painful Legs. Tested For Lyme Disease. Done Blood Work, Ultrasound Of Kidney And Liver. What May Be The Problem?

I was tested for Lyme disease and the blood work came back positive. I have been taking antibiotics for over a week now. I still feel like crap. I am still very tired, headaches are horrific and the pain in my legs is still there. I am however able to walk somewhat. but walking is unstable. What else can I do? Is there other treatments I can do? I was told I am stage 3, whatever that means? I am scheduled for an ultrasound for my kidney and liver in October. I did however have an ultrasound a while back and my liver was not right per the doctor, but that was way before the lyme disease results.