Yeah i have Gav.
It's not really a great experience, as in just the mental side of it.
You just have to remember they have seen all shapes, all sizes and many penis in their time and you shouldn't worry about anything.
It normally will be a male doctor, don't think females are allowed to do it anymore.
End of the day if you need to be checked out, or feel something isn't right down below you shouldn't ever hesistate to go.
Here's a video of a method to self check:
http://www.channel4embarrassingillnesse ... testicles/ after this book an appointment to go and see your GP.