Urine infection. Treated correctly!

My son was diagnosed with UTI when he initially complained about pain while peeing. Urine routine showed high pus cells, nitrite+, bacteria- present, he was put on antibiotics for 7 days (walamysin ds) which was sensitive against the bacteria. His KFT was normal and CBC did show low HB 10.5, low MCV 64.9, low MCH 20.2, high RDW CV 18.2, high ALC 7.3, platelet 491 and it was done during he was being treated with antibiotics. After 7 days we did another urine routine and culture and now pus cells showed 0-1, epithelial cells 0-1 but nitrite is still + and bacteria shows as present. What to do.. he doesn't complaint any pain now. But the knot (guilty)which he developed when UTI started is still there on left side of bladder. However it's not hard anymore and getting smaller. Before we visit the ped again , we wanted to make sure he is being treated correctly