lower abdominal soreness

I am not sure what it is but in my lower abdominals to left and right side of my Penis is sometimes sore. IT sometimes bothers me when I sitting down but never when I am standing up or even laying down. When I get up in the mornings it does not bother me until I start to eat or drink something or sometimes it just bother me. Some times it can get irriated when I am eating food or drinking soda. Well becaue of that I just stop drinking soda. I even went to the doctor and he told me it was not a STD and that maybe to lay off the wieghts. Well I did both but I still feel some discomfort. When I was talking to the physician he did say something about my urine was mixing with my sugar, something like that I can really remember exactly. Do I have a life threaten problem or disorder. I tried to diagnosis the problem myself by doing certain thingss. There are somedays it doesnot bother me and then there are days that it does bother me What can this be.