Spotting-implantation?

I starting doing some real faint pinkish spotting that only showed when I wiped and it's been on and off for 4 days. Not sure if this is implantation or AF about to start. My periods do not always start on the same day every month and sometimes have light discharge before period. This seems different. Today I noticed a small amount of mucus that was very light pink that didn't seem normal. Any ideas!? I'm really hoping been TTC For 8 months now.