Slow rising hcg

My first beta at 9 days after transfer was 148. I was thrilled to confirm I was pregnant. My second beta two days later only went up to 249, not doubling as they would have hoped to see. I go in again Thursday to see if my levels can double by then. I’m so nervous and having a hard time staying optimistic. We transferred our two remaining embryos and I just don’t think another round of IVF is in the cards for us. Anyone else have success with slow racing hcg?