Cramps and spotting after BFP

Hannah • TTC since 1/1/2016 • 2 losses • Endo - PCOS - Uterine Septum • Laparoscopy & Hysteroscopy 6/8/2018 • Not giving up 🙏🏻
So I finally got my BFP! But now I'm cramping pretty badly and spotting some brown when I wipe the past few hours. I understand that it could be a chemical, but has anyone ever had these symptoms and had a successful pregnancy? I'm looking for some positive feedback 🙏🏼