Help!! Brown discharge-tmi no pic

I've been having pregnancy symptoms for about a week or so with the exception of a missed period bc I'm on birth control and skipped a period, so I'm all confused.  I was extremely nausea last night and today. This morning I had stringy brown discharge when I wiped. I took a hpt last week and it came up negative. Is it worth trying another hpt? If so, when? What's up with the brown discharge? Never happened before! Thanks for all the help!