New to TTC, Implantation Bleeding? Dark brown and then pinkish brown. Help!

Liz

Hi Ladies! This is the 2nd month DH and I are TTC. I have been off bc pills for 6 months and have been tracking my cycles since then. I have a 30 day cycle and have been using clearblue digital OPK's to know when I am ovulating. Well, on 6/30 I got the blinking smiley face (high fertility) and BD'd the next day (peak day?) and 4 days prior to the high fertility day. Anyhow, today I am 7 dpo and had dark brown spotting this morning. I was checking my CM and when I pulled my fingers out it was a small/medium amount of dark brown. Then, several hours later i went to the bathroom and wiped and had a decent amount of pinkish/brown discharge on the toilet paper. This is abnormal for me. I dont normally spot 7 days before my expected period. Do you ladies think it could be IB or what? Has anyone else experienced this and had a positive test soon after? When should I test? Thanks to all for any insight you can offer!