Could i have a std?

Maybe. Maybe not.: A woman who's been having "s" with another person, might have allowed the other person to "t" some sort of "d" to her. So, a woman who has had sex (even once) with another person, indeed could have a sexually transmitted disease... But only if the other person had an std at the time of sex.

Please Clarify: Stds come through intimate contact with another person infected. There are viral, bacterial, parasite and other kinds of stds. There are twelve common stds. I come from the school of thought that every sexually active person should know what these twelve are and how and when to test for them.

Sexually Transmitted: Sexually Transmitted Disease. A person who does sexual-type activities with another person can give or receive (or both) germs that cause certain infections or diseases. Such diseases are called sexually transmitted diseases or sexually transmitted infections (STI). Usually, one can only catch an infection if the other person has that particular germ at the time of the sexual activities.