Hcg levels/ encouragement

So My last period was 1/26 and I have anywhere from 28-34 day cycles. I was waiting to do a frozen embryo transfer ( due to four previous miscarriages from natural pregnancies) but decided to test and got a positive pregnancy test 2/28. Had my hcg tested the next day at 4w6d was 78 which they said that they wanted over 100. I started crinone and 40mg lovenox and repeated the level at 5 wks 2 days and it was 188. They said it was was doubling beautifully and to come get a u/s 3/18 but I asked to have one more hcg level check which will be tomorrow am. My only pregnancy symptom is that I’m tired. I’m getting so anxious of what is to come. Has anyone else started with low numbers like that or have any encouragement is much appreciated bc it’s hard to stay cautiously optimistic with my history. Thanks for listening.