implantation bleeding help!!

I'm 12 DPO today and not due for AF until 11/4. I woke up this morning and after I wiped I noticed a little bit of brown/pink blood in the tp. With my daughter I never had bleeding so I'm hoping this is what's going on and not AF coming early. For those of you who have had bleeding how long did it last? it's been a couple hours and I keep checking like a maniac and there hasn't been anything else. thanks for the help!