Bent Penis

I am concern about my boyfriend penis I noticed that when he erects his penis bents now I am 2 years older than him and he hasn't have much experience I have found it strange for his penis to be bent like that since I never seen it before I try to ask him but men this dates don't want to talk about it I am worry that it might be something serious. I am doing some research on my own so I can try to help him out so maybe just maybe I can get him to go to the doctor I search online but the only thing that looks like it is like the picture in this page http://www.aafp.org/afp/990800ap/549.html figure 1 c which is called a Penile curvature now I don't know much about this is this normal in a 17 year old guy? or am I over doing the situation? I would highly appreciate you comments