14dpo and so many signs

Horrocks
I'm 14dpo. Due for AF tomorrow. Taken tests last 6 days and all negative. Started spotting light pink then brown since 12dpo and that has never happened before. I never spot before AF. I usually have horrid cramps for about 3 days before AF and NOTHING. No sore boobs or cramps. What is going on ?? Could it have been implantation bleeding on 12dpo? But its been 2 days so I assumed I would have gotten a positive hpt this morning. I feel like I'm out this month and I'm gutted. Anyone ever have this happen ?