It's a week before my period and i have brown discharge. it doesnt smell or itch or anything. i am on birth control and have been for over 3 years, i did miss a pill but i took two the next day. this is the first time this has happened to me, is this norm

Not unusual: Women taking the pill often have breakthrough spotting before their period starts. A brown discharge is simply old blood mixed with mucus. A woman's reproductive system is a very delicate and complex apparatus. Many things can affect its function. Emotional stress, change in sleep patterns, etc can alter your normal cycle. I wouldn't be alarmed, just keep track of things so that you can accurately describe changes to your doctor when you see them next