I am experiencing brown discharge that is thick and stretchy with slight itching. also my vagina looks a little swollen what could this be?

Not sure: Are you sexually active, engaging in unprotected sex, you may have an infection. However, are you using new tampons or feminine napkins or even feminine douches, these can all cause allergic reactions as well. BUT, you'll need you visit your primary care or Ob/gyn for a thorough exam including preg test if you are active, pap smear, and analysis to check for infections including yeast.