Hello I Have Been On The Birth Control Implant Nexplanon

Hello I have been on the birth control implant Nexplanon for over a month I'm also 7 months post partum and I just realized my breast are starting to leak like they did when I was Prego I also had light bleeding for two days and I'm tired all the time and nauseous . I took a test 2 and a half weeks ago and it said negative could my BC affect a test . I need help asap