Can Taking Amoxicillon Be Safe For Swollen Lymph Nodes In Neck And Muscle Pain?

I am 16 years old (about to be 17 on the 20th of this month), and for the past 4 months ive had these swollen lymph nodules in my neck. When I first noticed them i had developed fever and muscle aches as if I were really sick and my primary doctor insisted that i had strep throat (even though my throat didnt hurt and the test came back negative), he prescriped 500mg Amoxicillon and i finished the pills. Since then, ive occasionally had fever (low grade, comes and goes) bouts of nauesousness, lately some night sweats and fatigue. I just tell myself its stress, but the nodules have remained and are mobile and not painful and the same size and on both sides of my neck. A couple of months ago i also noticed pain in my lower right quadrant of my abdoman which i think is my appendix. Sometimes it is a dull pain, other times a stabbing pain. My symptoms usually come and go, and i recently noticed a bump by my appendix that feels similar to that in my neck. I dont know what wrong or if my neck and appendix are related but i would like all swollen nodules and pain to go away along with the occasional fever...

thankyou, Kiara