Has anyone ever had implantation bleeding?

Wh
If so, could you tell me a little about your experience? I'm 12 dpo today and I started having light cramping. My boobs have been sore for about 4 days. These are both normal symptoms of AF for me so I wasn't getting my hopes up. BFN this morning and yesterday. I went to pee about 10 minutes ago and when I wiped it was (TMI) brownish pink. Not at all what I'm used to with AF but just figured I was out this month. I'm not due for AF until the 15th though because I have such long cycles. Any advice is much appreciated! TTC #1 for 2 years and can't wait til it happens!