I had inguinal hernia on right side and now left side often hurts on same place but ultrasound doesnt show hernia. what could it be? is it dangerous? i also have varicocele in my left testicle. thanks?

It could be a strain /sprain. You dont need an ultrasound to diagnose an inguinal hernia. A good clinical exam will diagnose it. Sometimes a large varicocele can give a 'dragging' kind of pain. Use local heat and ibuprofen for a few days and if not better see a doc who will do a good hands on clinical exam. Wear a good supprt underwear for the varicocele. Hope you feel better