Help me

Ryn • I`m 19. Been married to my best friend/army infantry man since April 12, 2014
Okay so I have my period on the same time like every month. I'm on a type of birth control but it's for something to do with emotions or something (doctor knows I'm ttc and she said I will be fine to take it) but a week before my period I've had theis brown stuff that is thicker then blood coming out. Help me?