Worried

June 26th I had a miscarriage, I was roughly 11 weeks into the pregnancy when I started bleeding.  When I went to the hospital I was informed that the baby had stopped developing at 6 weeks.  No D&C was ordered since the baby was just a speck at the time it quit developing.  I bled heavily for a week and then the bleeding seemed to stop.  On July 4th I went back to work, I began to have crazy cramps that night at work, and the very next day, July 5th, I started bleeding heavily again.  I went to see my OBGYN on July 11th, on July 10th my husband and I were intimate for the first time since the loss.  Around July 26th, a month after the miscarriage I became insanely tired, I could hardly keep my eyes open no matter how much sleep I got the night before, 5 hours - 10 hours.  A week later, August 2nd, I threw up while brushing my teeth, and decided to take a pregnancy test to be on the safe side.  It was positive.  I cried of course, I couldn't have been happier.  I went to see my doctor on August 9th, and we figured that I couldn't be very far along and that there was no need for an ultrasound for another couple weeks.  She suggested that I see a high risk OBGYN, I have called damn near EVERY high risk OBG in town and nobody will see me, as they say I am NOT high risk having only had one miscarriage and am only 30.  August 11th I had some VERY DARK bleeding for a second, which of course FREAKED me out, but there was none after that except a small light pink spot.  I spoke with my doctor and she thought that it was just implantation bleeding.  She ordered me on bedrest and went out of town for two weeks.  My mind was not at ease with such a simple explanation, and so I found another doctor that could see me and went to see her on August 17th.  She was amazing!  She figured from the first day of my last period, July 5th, that I should be about 6 weeks pregnant, so we did an ultrasound, the baby measures 7 weeks and 5 days.  I did the math and figured that would put conception during my miscarriage, while my husband and I were certainly NOT having sex.  Is it possible that I am 6 weeks and that the baby is just big like daddy?  My husband is 6.3 280lbs.  Also there was no heart flutter that she could see. So we did blood work to test my hormone levels, I am going back today for more blood work, and then next Wednesday I go back for the results and another U/S.  I am naturally concerned, and of course scared.  How can the baby measure what it does and not have a heartbeat?  I have been praying like nobody's business since I had the bleeding last Thursday.  Up to today the only symptoms that I have of being pregnant is the HUNGER and the sleepiness.  No sore boobs like last time, no throwing up and just a little nausea here and there.  I am still ravenously hungry and could sleep all day every day, so I certainly feel like there is still something growing inside me.  I just want so badly for everything to be OK and normal, and to be able to carry our baby to term.  Has anyone else ever had an experience similar?  Where the baby measured farther along than it should and didn't yet have a heartbeat??