My birth control failed on Dec. 3rd and I took the off-brand of Plan B (same Levonorgestrel mg dose of Plan B One-Step) an hour afterwards. Fast forward to 9 days later (Dec. 12th) and I am experiencing spotting (which I've never experienced before in my life). I know everyone reacts differently to emergency contraceptive, but has this been known to happen? I'm a little worried here.