Your risk of HIV and other STDs is low. Your major exposure was unprotected oral sex since a condom was used for vaginal sex. Here are the facts:
1. Your partner said she was clean. She was probably telling the truth, most people do.
2. Your genital sex was condom protected and therefore no risk.
3. HIV is rarely, if ever transmitted through oral sex. The quoted figure for HIV risk, if one has oral sex with an infected partner is less than 1 in 10,000 and, in my estimation that is too high. Other experts state there is NO risk form oral sex. Neither of us on this site have ever seen or reading the medical literature of a convincing instance in which HIV was passed by oral sex. This includes by all of the people who had gum disease, etc.
4. For other STDs, oral sex is an inefficient way to transmit STDs. Of the bacterial STDs only gonorrhea and nongonococcal urethritis (NGU) are transmitted through oral sex; chlamydia is not and without an obvious sore or lesion on your partner’s mouth, the chances of syphilis and herpes is likewise tiny. If you had gotten gonorrhea or NGU you would have most likely developed symptoms of urethritis (penile infection). Even if your partner had an STD (any STD and it is likely she did not), most exposures do not lead to infection.
In your case, you had a single exposure. I would urge you not to worry. If you wish, you could go to your local STD clinic or health care provider to be tested at this time. The results of testing for bacterial STDs will be reliable.
For HIV testing, we would suggest that you get a test at 4-6 weeks after your exposure. In your situation, when the test result is negative, you should take the result as proof that you did not get HIV from your encounter. Some people suggest getting a PCR test for more rapid results. While theoretically appealing, these expensive tests are not recommended for routine HIV testing.
Hope these comments help. EWH