Hi Raquel-amez. I want to welcome you to our forum. I have a BS in medical technology (lab) so I can help you. If the urine is bright yellow, it's vitamin C. If it's an orange-brown color with foam, you're having liver problems which includes hepatitis A that you can get from poor hygiene at a restaurant. If it's just dark yellow, you are probably dehydrated.
Women occasionally have red blood cells (RBC) in urine just from exercise or a tear in the vaginal wall. The stuff that you see settling to the bottom can either be amorphous (just common junk that sometimes occurs) or a bacterial infection. Since you have blood in your urine, a bacterial infection is certainly a possibility.
To give yourself peace of mind, go to your physician's office and tell them you want a copy of all your lab work from that visit. On your blood tests, if your creatinine and BUN are normal your kidneys are fine. If your bilirubin, AST, and ALT are normal your liver is good too. If your white blood cell (WBC) count is within normal range you're good, but if it's high you have a bacterial infection even if you're not having pain.
Urine should be sterile (no bacteria). If you had a urinalysis during your last visit, check if the following are abnormal: leukocyte esterase, bilirubin, protein and if WBCs, bacteria, and red blood cells are present.
I think you should schedule a visit to see your primary care doc and ask him/her to order another urinalysis plus culture & sensitivity on your urine. For a urine culture the tech puts some of your urine on a petri dish and sees if bacteria grows. The sensitivity is done if lots bacteria grows and tells the doc what antibiotic will work best.
Sorry for such a long answer! Love, Butterflake