Blood in Urine, no pain. Lightheaded, weak knees

I am a 21 year old female. I have a history of kidney stones as well as UTIs.... Lately I been having these strange bouts of lightheadedness and weak knees. I haven't thought much of it until today when I had a new symptom occur. I used the bathroom and looked down and saw BRIGHT red urine. Now I have also noticed that I have a plusing warm sensation on my right side where I normally have pain for kidney stones. But the urine does not burn me and I am not in any pain, just the weird pulsing and warm feeling. I have had kidney stones as well as UTIs often enough to know that I have never had any of these signs or symptoms with either one before. I am worried because all I have found upon research says these are signs of cancer?? I have not been to a doctor. Can anyone tell me what this is a sign of? Thank you
~ Worried