Hi,
First, you need to identify why you have yellow eyes: possible
liver problems. Do blood work and liver enzymes.
Lower
back pain might be related to infection or uro-genital tract. This might explain leakage. - Do urine analysis, urine culture, and culture of spermatic discharge.
Once the results of analysis are in, you should start treatment with antibiotic. While you are on therapy, try not to masturbate.
You are too young and will overcome to these problems very quickly but need correct medical evaluation and treatment.
With regards to diet, try to eat healthy and fresh foods, fruits and vegetables, avoid processed foods and high-calories foods.
Try to avoid also energetic drinks, caffeine drinks, alcohol,
smoking, or other illicit drugs.
Stay physically active, do some sports (running, playing soccer or basketball or other sport you like).
Hope it helped!