Confused?

How can I have very strong positives but my HCG only be at 44? We can’t go off my LMP because that would put me at 5 weeks but based on bleeding I had and US and bloodwork my dr says I am very very early pregnant, like under 4/3 weeks? I go in on Tuesday for more bloodwork. On Thursday my HCG was 22 then on Saturday it was 45. Will she be able to tell me how far along I actually am? I don’t know what the heck is going on as I was told I was having a miscarriage but then my levels went up and the dr said that was a good sign....