LMP "inaccurate", low hcg but increasing regularly

I took a home pregnancy test two weeks ago and it came out positive. I arranged an appointment with my doctor the following day where she did a urine sample and blood test. My LMP was 09/28(which was about a week late) but my HCG levels were only 133, the doctor said that I was most likely miscarrying again (I had a miscarriage in February 2010). She scheduled for me to have blood work done again on Nov. 3rd and 5th, they came back at 447 and 898. Today I started spotting and am having mild cramps so I made a trip to emerge. The doctor in emergency requested a transvaginal and abdominal u/s. Both results came back with no fetal pole, just a gestational sac and a yolk sac. He told me it was too early to tell but I am positive that my LMP was 9/28 which would make me over 6 weeks and far enough to see a fetal pole. Any similar experiences?

[AnnieBrooke]

Maybe you had a late ovulation and are really only about 5 weeks along.  

[AnnieBrooke]

Maybe you had a late ovulation and are really only about 5 weeks along.  

[charmander]

Thank you AnnieBrooke for replying. I have not seen any blood since this morning's emergency visit. I am hoping that I did in fact ovulate late. I will post an update once I receive an update with my family physician. This waiting period is messing with my sanity, I am praying for some good feedback