Brown discharge?

Hey ladies i have a question so i went to the doctor Tuesday and did a normal checkup and she wanted me to take a pregnancy test just to make sure. That came back negative. Now all last week I’ve been taking pregnancy tests because i am paranoid and i was feeling to well body aches, bloated, nausea, breaking out and etc. So this week i am suppose to start my period and yesterday when i went to the bathroom it was brown discharge on and off the day which was light as well. Last week i felt like my period was starting soon but idk i want to take a pregnancy test but i just went to the doctor Tuesday and that came back negative. I am on birth control my 2nd pack which i take everyday. Should i worry about this?