Having condoms on you at all times can make it easier to negotiate condom use with your partners. Remember to also use a water- or silicone-based lubricant, to prevent lesions during vaginal or anal sex.
If you do not like using condoms or if your current partner tells you that wearing one makes him lose his erection, there is no need to panic. There is plenty of sexual play that you can do without a condom, that entails little risk of infection.
If you did not use a condom, or if the condom broke, emergency contraception (also known as the morning after pill) can prevent an unplanned pregnancy if it is taken quickly (within 5 days).
There is also post-exposure prophylaxis (PEP), a treatment option that is recommended after unprotected vaginal or anal sex with a partner who is HIV-positive or whose status is unknown.