Kidney Problems

I have been noticing for 2-3 months that whenever I masterbate i find blackish substance on my penis  around the tip. I don't know if the discharge is from penis or from the skin. But the tip area has a blackish substance. What is it? And is it concerning I have a history of masterbation and have black lesions on my penis too. Tell me what it can be. I have attached a pic.

Hello, I have been on antibiotics since the last two weeks for burning sensation and frequency today I feel improvement in burning but frequency is still present.

Hi I have small cyst in my kidney, I'm going to take whey protien to meet my protien goal is that OK to take whey protien having cyst in kidney anyone please respond. Thanks in advance

This morning something like worm came out through my urine path. It came out once before at night as well. Is this serious concern? I m very worried

Infection in Penis head and fore skin. Last 3 days, i am noticing itchy and red spots. Also from last two days there is tightness in foreskin.

Hi doctor. My 4 year old son passes pink colored urine after eating beetroot. Is this normal. Can i continue giving him beetroot or it may damage kidney. Please advise

I am facing urge to urination, burning and lower abdominal pain. Already taken Alkacitrol and antibiotic but no relief. But when I took sildenafil tab, I got relief. No burning and no urge

This is my USG report.. 1. Is there found any kidney stone ? (0.2 cm and 0.3 is stone?) 2. Regarding ovaries, am i pregnant? (I have kidney stone 0.489 cm in the month of June)

I am 18 years old boy ...I feel unable to pull back my foreskin ...it's not like completely closed but it's like mild phimosis...it can be pulled to less than half of penis head or glans and when it's not erect it can be pulled back to more extent but not completely..also after oiling it comes more back but it's not normal for long run ...also I am not able to touch my glans when foreskin is pulled back...I feel very uneasy when touch it at some areas I can touch it but not as a whole or at edges... TIGHT FORESKIN AND SENSITIVE GLANS AT AGE 18 ...TOGETHER IT'S PROBABLY PHIMOSIS

Since 10 days I am having mild burning and pain while urinating but my urine report is normal and ultrasound report is also normal. What could be the cause? I am worried Also I'm married