I am not sure whether she was a 3rd year student doctor, or a qualified doctor who has spent 3 years practising (so that would be 2 years as a foundation trainee and one as an SHO).
When I did my medical degree we did not see any patients for 3 years. The first 2 years were the basics of anatomy and physiology and then I did a masters in neuroscience.
Met my first patient in year 4 and at that stage I had a high degree of knowledge of normal anatomy, biochemistry, genetics etc but knew very very little about disease.
I went to Cambridge which is an unusual course as it is far more academic and less patient centred. When I taught at Manchester University they phased in patient contact in year 3, but the first 2 years had an integrated approach so for example they would study the anatomy and physiology of the stomach, alongside stomach cancer and ulcers.
If this is some 3rd year student you are being incredibly unreasonable. The whole point of being a student is to learn things and that GUM clinic was her opportunity to learn about GUM.
If it is an SHO then she really should know it, but from what I have read it looks like she was a year 3 student, so you are probably one of the first patients she has ever met.
She did not harm you in any way. She did not have the opportunity to be clinically negligent as she was there as an observer and so did not treat you.
You remind me of one of those aggressive drivers who toots their horn at some poor sod doing 15 in a 30 when it is obvious they are a learner driver in a driving school car.