nervous hcg levels

Erin

so had a hard time getting pregnant . Doctor was surprised to hear that I am. had a blood test on Wednesday for my HCG and progesterone levels came back HCG was 2303 progesterone was 19. Had done again today first progesterone is 23 in HCG is 39/40. She said to proceed with caution but not to get too worried what does that mean should I be worried or does it sound okay has anybody else experienced this? I know that number should double and it did not so that's what scares me. Thank you for any help. Test was 4pm Wednesday and noon today...so 44 hrs.