Hi. My name is paul.. I have gastritis and i feel pain and itching in my stomach, back, pelvic region and Penis. The worst part is that it causes my Penis  to shrink and now it has become small,  i also discovered that my semen is now little and watery.
Degree understand your concerns went through your details. I suggest you not to worry much. I suggest you not to go with wrong information. Anybody problem is supposed to affect your spirit. That does not mean that a problem like gastritis can shrink your penis. Absurd. Semen thickness depends on so many factors like stress, deny Chat Doctor. You are obsessed with sexual thoughts and worries about sexual health. Anxiety shall be the resultant problem. Concentrate on your studies or career and let sex take its own course. If you require more of my help in this aspect, Please post a direct question to me in this website. Make sure that you include every minute details possible. I shall prescribe some sexology related psychotherapy techniques which should help you cure your condition further. Hope this answers your query. Available for further clarifications. Good luck.