No. Like all sexually transmitted infections, HIV cannot be 'created', only passed on. If you are sure that your partner does not have HIV, then there is no risk of acquiring it, even if you do have unprotected sex (whether it be vaginal, anal or oral). However, pregnancy and other sexually transmitted diseases (if your partner has one) remain a risk, so you should still use a condom or other suitable form of birth control wherever possible.

Whilst research suggests that high concentrations of HIV can sometimes be detected in precum, it is difficult to judge whether HIV is present in sufficient quantities for infection to occur. To guard against the possibility of infection with HIV or any other STD it is best to practise safer sex, i.e. sex with a condom.

Lesbians/bisexual women are not at high risk of contracting HIV through woman-to-woman sex. Very few women are known to have passed HIV on to other women sexually, though it is theoretically possible if infected vaginal fluids or blood from an HIV positive partner enter the other woman's vagina (perhaps on fingers or sex toys).

Although it is possible to become infected with HIV through oral sex, the risk of becoming infected in this way is much lower than the risk of infection via unprotected sexual intercourse with a man or woman. Still, take precautions such as using a condom and avoiding oral sex if either partner has cuts, bleeding or an STI.

You can contract HIV from someone who has been tested negative during the window period.

There is not a cure for HIV disease. A variety of drugs are used to slow down the damage that HIV does to the immune system. When they are effective, these drugs reduce the amount of HIV in a person's body. However, the drugs do not totally rid the body of the virus.

HIV anti-viral drugs slow down the replication of the virus and the destruction of the immune system.

Firstly – try not to worry. If you've only recently had a risky sexual (or injecting) encounter, then you might have to wait before you can have a test anyway. Remember – the vast majority of HIV tests are negative, but if you want to be sure, a test is the best way to put you mind at rest.
It is generally best to wait at least 6 weeks before taking an HIV test, although waiting 3 months will give you a more reliable result.

Once HIV enters the body, the immune system starts to produce antibodies – (chemicals that are part of the immune system that recognize invaders like bacteria and viruses and mobilize the body's attempt to fight infection). In the case of HIV, these antibodies cannot fight off the infection, but their presence is used to tell whether a person has HIV in his or her body. In other words, most HIV tests look for the HIV antibodies rather than looking for HIV itself. There are tests that look for HIV's genetic material directly, but these are not in widespread use.
The most common HIV tests use blood to detect HIV infection. Tests using saliva or urine are also available. Some tests take a few days for results, but rapid HIV tests can give results in about 20 minutes. All positive HIV tests must be followed up by another test to confirm the positive result. Results of this confirmatory test can take a few days to a few weeks

Experts agree that one HIV test is not enough. A series of tests is required to assure that you are indeed HIV negative. It is recommended that you be tested at the time of exposure, 6 weeks later; 3 months after exposure and finally some even believe that a test at 6 months post exposure is necessary.

Yes, if you are tested during the window period. (See Q on window period)

There is a short window in time that it is possible to test HIV negative and still be HIV infected. When HIV initially infects the body, your immune system begins to develop antibodies to the virus. It is those antibodies that HIV tests look for when you get tested. However,it takes some time for enough of those antibodies to be produced for an HIV test to detect. Therefore if enough have not been produced when you are tested, the test can be negative when in fact you have been infected. Keep in mind that during this window, HIV can be transmitted from one person to another. Safer sex practices must be employed.

Casual sexual partners who are having intercourse should always use two forms of birth control—one to prevent unplanned pregnancy and another to prevent STI transmission (dual protection). The best combination is to use a barrier method, like a condom, along with a hormonal method, like the birth control pill. Condoms are the only form of birth control—other than abstinence—that can protect against STIs.

There is no age limit to buy condoms. Anyone of any age can buy condoms in a chemist or get them at a health clinic.