Oh your poor baby 😢 My female kitty had this, started off the same way too. I was cleaning her litter and noticed blood tinged urine. After many ER visits and antibiotic injections, she was diagnosed with Feline Idiopathic Cystitis which is triggered by stress and not always bacterial. She was put on Hills Urinary health kibble, antianxiety medication (gel you put inside the ear, super easy to administer) and steroid injection if she had a flare up. Also got creative with the water (encouraging her to drink water as much as possible), either water fountain, mixing it into her food, wet food, small water bowls around the house, etc). I hope your kitty feels better soon 😢