I have had pink/watery or brownish discharge for a week now on and off? and ideas what it is?

Pink watery d/c: May be vaginitis, infection like mycoplasma, ureoplasma ( not usually tested) trichamonas, chalmydia ( if sexually active0 or BV as well ( though that is usually with fishy odor and grey yellow. May also be spotting /implantation check HCG or just spotting from variation in period especially if on BCP follow up with doctor /urgent care