Hello. A delicate question: I've noticed watery discharge for three d…

Hello. A delicate question: I've noticed watery discharge for three days now, colorless. I don't feel them flowing or anything, I just go to the toilet and my underwear is damp even though I try to hold it in. When I wear pants, they get slightly wet too. Can this be caused by something leaking? Would there be any indication of this in a urine test? My last urine test was fine. Also, my lower back started hurting suddenly, without any prior warning. Has anyone experienced this before? Can you explain to me what's happening in simple terms? ?