Suggest Treatment For Erectile Dysfunction

Good morning doctor. I m 40 years old male. I always living with family in every duty station and going well married life since last 20 years of my married life. I have two kids 17 and 12 yrs old. In Oct 2014 I have posted in South India and shifted family in Uttarakhand due to education of children, On 15 Feb 2015 I came leave and during intercourse I found my penis is not erecting fully as earlier.. (Erecting but not just like a hard and feeling loose).we both surprising ..how it happened...Yes I did musterbating before 2-3 week and regularly 3-4 days only. Also during journey in Train on the night of 14-15 Feb i have seen small XXX movies in mobile atleast 3-4 hrs. Is problem arise from that causes..Now I want to how I can satisfy from this problem..please suggest me what type of medicine should be use. I m physically and mentally fit. there is no another problem with me.