hey Alicat,
when i fell pregnant with my DD my blood test was taken 14DPO my HCG level was 24, i was so worried but was told time and time again that it is not so much where the levels start but how they rise that is the important thing. I know that now as DD is almost 2 and perfectly healthy. I know it doesnt help much when youa re stressing out but if i read your post right your HCG levels have almost trippled in 3 days?? I am not a Dr but that sounds good to me!!
Please try not to stress ( i know way easier said than done) but your little bean would like a stressfree mamma!
Good luck!