I didn't feel anything for implantation - I didn't know if it worked or not till AF showed up or didn't. Sorry. I think you're a little early though - IIRC implantation is 6-10 days later. Sometimes there is spotting afterwards, but again, I never got that either. Good luck, and hope this is your month!
"Every saint has a past and every sinner has a future" - Oscar Wilde
It still might be too early to see signs of implantation, here's some information I found for you:
10 Most Common Signs of Pregnancy:http://parenting.ivillage.com/pregnancy/pfirsttri/0,,cnmg5gvn,00.html?rand=1
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