Is it possible to be 14 weeks along, but it not be detected in a pelvic exam in which the doctor is looking for signs of pregnancy. Could the baby be that far behind that the doctor wouldn't detect it at all?

Also, can you be pregnant but have no hCG detected in your blood on several quantitative tests?

I'm just very worried and can't seem to get it out of my head that I might be pregnant. The last time I had sex was August 18, and a condom was used (it didn't leak or slip). I had about 3 quantitative tests done up to what would've been 9 weeks along, and they all said no hCG was detected, or <1. At what would've been 14 weeks I had a pelvic exam, and the doctor did not feel anything different about my uterus. I just want to know if it's even possible to be pregnant with no hCG detected, and if the baby can measure so far behind that it wouldn't be detected in a pelvic exam at 14 weeks.

Thanks!