I am 9 days dpo (has sex 2 times during fertile window, 10 and 11days ago) last night I got nauseated, my breast are tender and my back hurts. I have a pretty regular cycle, that i should start in 5 days. Last night I wiped and there was light pink blood. I went to bed and there is no sign of any bleeding thing morning there is nothing, only yesterday when I wiped. Could this be implanting bleeding? If so, how long should I wait to test? Thank you.