I Have Enlarged Lymph Nodes In My Neck, Groin, Arm

I have enlarged lymph nodes in my neck, groin, arm pits, and by my collar bone. Took antibiotics for 10 days. No change. I had a biopsy on the one near the groin. Not cancerous so they think it is a virus or fungus infection. Symptoms are I seem more winded when I exercise, feel more bloated when I eat, my sinuses bother me more (seems like allergies) and my skin itches. I still have the same amount of energy, no night time sweats, and have actually gained 5 pounds. How can I narrow down what virus or fungus it may be?