5weeks... bleeding clots, minor cramps and slow rising hcg !!

I'm 5w4d today...and I had red bleeding with some clots and minor cramps.. Went to the doctor and she did and ultrasound and said my gestational sac was growing perfectly but my hcg levels were doubling slowly..

Here are my hcg levels so far..

13july - 10dp5dt - 41 (15dpo) 3w5d

15july - 12dp5dt - 123 (17dpo) 4w (30 hrs)

18july - 15dp5dt - 299 (20dpo) 4w3d (56 hrs)

24july - 21dp5dt - 1785 (25dpo) 5w2d (55 hrs)

26july - 23dp5dt - 2439 (27dpo) 5w4d (133 hrs)

As u can see.. My doubling time went down from 55hrs to 133hrs.. I passed red clots..but only once..and no bleeding after tht.. My sac shows a gestational sac and yoke sac growing perfectly as it should be.

I don't know what is happening.. I'm.scared to death.. I don't wanna lose this baby.. If I do this will be my 5th miscarriage in 2 years.