Possible miscarriage

Has anyone been told they may be miscarrying due to their levels not doubling in 24 hours? Has anyone gone back after that & found out it’s 48-72 hours instead of every 24? Just looking for a little hope..

My numbers haven’t dropped but they haven’t doubled either, they only went up a smidge..

No others signs of miscarrying. Some spotting the other day but no pain & not enough to fill a pad.