Hello dear ,,,really sorry to hear your problem,,,,,i think you have two problems going side by side ,,,,,first is your lymp node infection ,,,,,for this i would suggest you go to doctor,,,do puss culture and sensitivity of puss and take medicine accordingly,,,,,,,,
Secondly increased apetite ,,,,
weight loss,
night sweats are a few sign of thyroid problems so better do your
thyroid function tests also to be on safe side,,,,,i hope my answer is helpfull take care stay blessed