Im sorry I dont have much info to offer you hun BUT dont loose hope if the numbers are going up! Just try to not stress over it (I know thats impossible) and see what happens with the next set of numbers..... Wishing you tons of Super Sticky Baby Dust!!!
Some hcg levels go up every 72 hours, and don't always double, I think if they go up by 60% their still good and rising. So it may all of a sudden spike and what not soon. Don't let your doctor try to do anything to make a miscarriage happen, or the d&c... I think thats what it is. Tell her you want to ride it out to see. Atleast get to 8 to 10 weeks before deciding anything. That way when 7 weeks rolls around you can get an u/s to see!
The time frame for doubling can be as much as 72 hours. In 48 hours it needs to double at least 80% to be a viable pregnancy.