Thanks so much HowardH... I really hope this will be the case with me.
You describe a virtually zero risk sexual lifestyle with regard to HIV. And unless your latest partner is bisexual, an injection drug user, has a history of imprisonment, or other high risk factors, the chance he has HIV is very low. And even if he were infected, a single episode of unprotected vaginal sex carries a transmission risk of roughly once for every 1,000 exposures.
And yes it is too early for symptoms of HIV. Typically 10-14 days and never before 7-8 days. And your symptoms aren't typical for a new HIV infection anyway -- no fever, no sore throat or skin rash, etc.
Although the overall chance you have HIV is therefore very low, you should be tested. Every non-monogamous sexually active person should be tested for HIV from time to time, like once a year -- it's very unlikely to be positive, but better safe than sorry! While you're at it, get tested for the routine STDs as well: chlamydia, gonorrhea, and syphilis. The risks of these is far higher than for HIV!