AF late + spotting =pregnant??

I'm on round 2 of Femara and AF was due on the 6th. I took a test however on the 8th that was negative and I'm spotting but still no period. Last month on femara, my period was 3 days late but now I'm almost past that. My doc said if my period doesn't come by next week to call and she will give me provera. Has anyone been late with spotting on femara and actually been pregnant?? I'm getting impatient and at this point I just want my period to start if I'm not pregnant. But of course I'd rather be pregnant!