Theres a small hard bump beside & btwn vag and anus. it's doesn't hurt, but what is it? i get tested for stds regularly, so no stds. ingrown hair?

Skin tag : it could be something as simple as a skin tag or blocked sebaceous gland. The best way is to have a doctor look at it or present a picture of it here

Get an exam: There isn't a way to know what this is without doing an exam. A likely cause is a Bartholin gland cyst. The Bartholin gland is in this area and swell and form a hard nodule. Sometimes these get large and painful and have to be drained. Best wishes!