TMI-- implantation bleeding?

Samantha

3 days late-- never late! Just had intercourse and noticed light pink discharge right after. According to my cycle I'd be 4w2d. Could that be implantation spotting or is AF showing her ugly face? I know my best bet is to wait and see, but I've never experienced the light pink CM before. Also I have ZERO symptoms-- not even AF symptoms. Anyone else experience this before a BFP? I took a test last week and BFN. Going to the store later to grab more tests.