Help Anyone??

As
I just missed my period 2/13/17 had my first beta on 2/11/17 and it was 42.6  a day later 2/12/17 it was 68 and 3 days later 2/14/17 it was 300 yesterday would of made me 4weeks and 4 days is that good or bad as my doctor said it's low and my due date is 10/21/17 ??