Well... the diagram is a really simplified version of the what is down there. The whole area is not exactly all neat and pretty with three perfectly defined holes etc. There actually lots of curdley bits and skin folds. Skin folds and bumps and lumps are quite common between urethra and vagina. The clitoris itself is rarely visable is a big lump like that diagram suggests. It is often covered by folds of skin and may not appear until stimulated.I noticed something about this diagram that made me kind of uneasy. After I saw this, I checked myself and noticed that my ehm, clitoris is below my urethral opening. Is that bad? ' I had a pap-smear about a year and a half ago and they didn't say anything about it but it still concerns me a little bit. x.x
Having said that, the research that I have done suggests that on some occasions the clitoris can turn up below the urethra. This is not something to be concerned about unless you feel that you are not getting adequate function. If that is the case then you need to visit a gyn. Having it below the urethra and closer to the vaginal opening means that you are probably more likely to experience orgasm through vaginal intercourse because of it's proximity to where all the action happens hence, greater stimulation.
What you need to determine is if it is your clitoris that is below the urethra or just a skin mottle or some such like that and only self exploration will do that for you. Regardless, if you are getting adequate function there is nothing to be concerned about.