Hello. Am in serious trouble from past 4 years and I see no hope. I am a 22 year old male. During my puberty every thing was normal. Hormonal changes in my body were completely normal. My muscles. Body hairs. Voice deepening every thing took place. I was like a normal male attracted towards, girls, having good sexual instinct and completely active. But when I reached 18- 19 years. Suddenly my sexual instinct started declining, my libido became very low, I started feeling lethargy constantly with lower back pain. My sperm thickness got reduced. I was shocked with the fact that how it could occur at such age. But the truth I am in serious trouble. Have never been in depression, neither I have obesity and I am very active person. From past four years I am suffering with extreme low libido. What could be the reason behind it? My family doctor made me do some urine test and he told me that I am totally fit. But it know that something is seriously wrong.