Need help hcg levels only at 30

So last night I went to the hospital because I was having some cramping I told them I was pregnant I got a VFL two days ago hospital confirmed I am pregnant but told me I may be only a week how is that even possible to find out it only a week my HTC levels are only at 30 and told me I need to do bloodwork in 3 to 4 days to see if they’re going up to make sure the pregnancy is going to be viable Has anyone had this happen before I Estimated I’m 2 weeks and 3 days