Started my period 8days early brownish lasted one day then stopped for 1day then came back 1day then stopped for almost 3days now I'm bleeding again?

Several possibilites. certainly if there has been other issues, bleeding problems in general or liver or blood disorders that could be a cause, or hormonal changes AND ibuprofen certainly predisposes to bleeding. But there's a lot of other groups of possibilites. http://www.nerdpocalypse.net/diseases/spotting%20between%20periods.html.