Slow rising HCG

I had a miscarriage in March at 6.5 weeks. My body was very stubborn normalizing to zero even after finally needing to have a d&c, still took a month to clear. Been trying again for a few months and finally we're able to be pregnant again 🥰 Currently am 6 weeks and had quant levels done last week and they rose slower than anyone would like. Levels in 48 hour increments we're 1331, 1753, 2230. My OB calls them suspicious. Rising but slowly. I have an ultrasound scheduled for this coming Friday, as he wants to be certain there is something to see. I'm praying and staying positive that hopefully everything will be fine and great.

Anyone had any similar pregnancies with their HCG? I'm open to good and bad stories as that's the truth of it. Any help is appreciated.