What is wrong with me?

Ok so a few days ago i went to the bathroom and in my underwear was like some slimy stuff. idk what it is but it is NOT blood. its been like that ever since and i have to put a piece of tissue there just incase. it looks like doo doo and its really brown and slimy and every time i wipe in the shower really really good nothing shows up on the rag. and when i wipe with tissue nothing shows up but little brown marks like i just did number 2. can someone tell me what this is coming from my vagina. thanks. serious answers plz