Birth control after birth

Okay so I went to my 4-6 week check up at 4 weeks and she told me I could put on my patch the same day even though I haven't had a period since birth so I put it on the next day after I picked it up and it's been two days since I've had it on and now I'm having brown discharge after I pee when wiping what's does that mean? Am I about to start my period or...? I thought I only supposed to got a period when I'm off the patch for a week...