<s>[INST] i am 20 years old. i got my testicles kicked ,about 3 weeks ago,it was really painful but i did not notice any change in their color or appearance , but since that day my erection became weaker,and it takes more time to get erected, Is there any relation between what occurred to my testis and erection ?.and  if so is there any way to get a normal erection as i used to have?. [/INST] There are many possibilities. They range from 1) merely a bit of anxiety, 2) a bit of irritation and pain that mentally makes it hard to relax to Serious structural damage with lower testosterone level. Frankly a lower testosterone level probably cannot have an effect that fast nor is it likely to occur. Everything about the testicle can be examined with some simple tests (testosterone blood level + ultrasound). </s>