You seem to have learned my answers by reading the forum, so you won't be surprised by my replies. (The reason threads stay available is so that people in your situation can learn what they need to know without having to ask their own questions.) The quick reply is that your risk was too low to even have HIV testing, regardless of your symptoms. Interesting to see those statistics on HIV in Scotland; that's less than one third the rate in the US. And surely the large majority of those women are commercial sex workers, injection drug users, immigrants from HIV endemic countries, or partners of known HIV infected men. The chance your sex partner had HIV undoubtedly is even lower.
To your questions:
1) Your symptoms don't sound like those of HIV. Even if you had classical symptoms of ARS, that probably would not be the cause in the low-risk scenario you describe. However, if you really had blister-like lesions of the penis, genital herpes seems a strong possibility and you should address this with your doctor; or visit a GUM clinic.
2) I agree with your doctor. Around 90-95% of people with new HIV infections have positive blood tests by 4 weeks. If you add that statistic to the low likelihood your partner had HIV, and the low chance of transmission even if she did, the odds you have HIV are no more than 1 in several million -- in other words, zero.
3) I have never seen such a case. It can happen but is rare.
Bottom line: Forget HIV. Address the herpes possibility with your doctor or a GUM clinic.
Best wishes-- HHH, MD
Just to add that in UK, there is an anonymous unlinked HIV screening programme, where all blood samples on people who attend GUM clinics, other clinics and antenatal clinics are anonymised and then tested for HIV. This does not require patient consent as it is unlinked and anonymised . However this gives an idea of the actual number of people who are infected as oppsed to rates among those who come forward for testing. Based on this info, it has been estimated that one-third of people with infection dont know their status. This will increase the figure of 1500 by one-third, but still miniscule when compared to the overall population. The HPA websites also state that the majority of people who acquired infection heterosexually did so outside UK, mainly in Africa.