Female Cat's Urinary Discharge

I found some white discharge with clumps of blood in my female cat's pee last Tuesday morning, 17th May 2022. I am obviously shocked and worried. What is this? Some infection in her urinary tract?

She was in heat about a week ago. A few days after that I started noticing a tinge of red in her urine. And then this discharge pictured above.

She appears to be her normal self all this while. So I did not suspect anything out of the ordinary. She still drinks a lot of water, as she always does, and her appetite is good.

As of today, her urine seems to be back to normal now. But there still seems to be clumps of blood in her pee from time to time, not often.

By the way, this is not the first time that this cat is peeing 'red' urine. It first happened about 5 or 6 years ago. It usually disappears after a few days without me doing anything.

Update: 25th May 2022

My cat seems to be back to normal. No traces of blood in her urine anymore over the last couple of days. I think there might have been some kind of infection around her uterus or urinary tract.

I have been giving her Himalaya Nefrotoec (a kind of herbal antiseptic) for about a week now. Only one tablet per day (instead of two as written on the bottle), as she is quite fussy with anything force fed.

I will continue with this medicine for about another week, hoping that this medicine will flush out whatever stones that might be in her. All she has ever eaten since she was little was dry kibble cat food, and they are bad for cats' health as they will cause the formation of stones. I wished I had known this earlier.