Large amount of blood in urine all other urine tests clear. took antibiotic for week. still there. no kidney pain. blood work ok. what's next?

Urinary tract eval: If you mean that you can see a large amount of blood in your urine, see a urologist right away. If instead you mean that there's a large amount of microscopic blood (from a urinalysis), then your urinary tract (kidneys, ureters, bladder) should be imaged. This can be a ct scan, ultrasound, plain x-ray, etc. Sometimes other urine tests are done. Your doctor should be coordinating the evaluation.