There is a possibility that you are pregnant if the patch wasn't working to the extent it is supposed to be working. You would not be feeling symptoms 3 days after the fact. And about taking the patch off at the posibility of being pregnant, I'm not sure about that one. Maybe call the doctor and ask? I know that there have been babies conceived while on birth control, the mom keeps taking the birth control and then realizes a while later that she is pregnant and those babies turn out okay. But you may want to just double check. Sorry I couldn't help more.
EDD with baby #1 for hubby and I September 21st, 2003! It's A BOY!