Now what? Blood in urine

I am a 52 year old female. I have a complex medical history with autoimmune diseases, GI issues and thyroid cancer. I had a radical hysterectomy 5 years ago for endometriosis. 10 days ago I suddenly saw a lot of blood in my urine. The blood comes and goes, sometimes even leaking onto a panty liner and sometimes contains small clots. Initial urine culture showed large blood, no leukocytes, trace protein and multiple flora. Blood labs show normal kidney function. My symptoms have been going more often, feeling like I can’t empty 100%, significant pressure in lower abdomen, no appetite and exhaustion. Yesterday I had a cystoscopy. Dr. Said he didn’t see anything to even biopsy. He said he saw blood and irritation at the bottom of the bladder and told me to use vaginal estrogen cream to treat and see him for follow up in January. My spidey sense tells me there’s something not right. What do I do next? I’m not fearful that something is wrong, but I am terrified, frustrated and angry that something is being missed and it’s up to me to convince a doctor to keep looking 🙁