Talk to Gynecologist on Gynecological

Hi there! I am having an history of 2 miscarriages at 7th week of pregnancy. I have conceived for the 3rd time now. My due date for periods was 7th of August, but i was late so i did upt on 17th August and it came positive, on 18th august i went for serum beta hcg and it came out positive too. At that time my pregnancy level was 189. My doctor prescribed me duphaston and adfolic. And 2 injections, GHC 5000 and Clexane. I started taking them on 18th August,, on 22nd August i had spotting. I went to my doctor, she did an transvaginal ultrasound and told me that she didn't see any sac or anything neither in my uterus, nor in my tubes. She asked me to repeat serum beta hcg. I repeated it on 25th of August and my hcg levels was 54,180. So i waited for next ultrasound to be done. I had an abdominal ultrasound done last night, which was 28th of August and still my doctor was unable to see any gestational sac in my uterus or outside. I am soo depressed, can somebody help me in this regard?? W