Suggest Remedy For Slight Rash On The Neck

hello, i am 18 years old and about 168lbs. i started fruta planta 4 days ago and on the 3rd day i realized a slight rash on my neck, it doesnt itch but its just there. i also saw a mini "knot"( like a lymph node) protruding on my neck near to the rash. none of these are actually painful or itchy. I was just wondering if I should be concerned.