Possibly pregnant again

I am waiting until the cheap pregnancy tests come in the mail today haha. But I feel pregnant. I don't know. We had unprotected sex the 2nd day of my period, that was 3 weeks ago. Anyway, no matter when I become pregnant again, I can't imagine loving a baby as much as I love my son. I also would feel guilty for doing anything to take time from him. He is my world. Does anyone else feel this way?