You really need to see your LLMD. This could be from restarting your abx and be an allergic reaction to one or both of them. Itching all over is a common sign of this, not for lemon juice. Last time I had penicillin, I was itchy all over and it was going down my ears and down my throat!
Not good!
It could easily be something else, but for your own safety, you really need to see your doc.