Sorry I'm not much help here but all I could really say is that if there was a problem, then I would think that your dr would have said something by now. As long as the bub is still growing and there doesn't seem to be a problem I wouldn't be worried.
I lost 5 kilos between finding out I was pregnant at 6 weeks and weighed myself today and have only put that back on plus 1.5 kgs. The midwife measures me every visit and I'm still growing.
As long as the bub is moving, that's good. Sometimes I'll go a couple of days and not feel a thing, other times it goes crazy. I guess it would also depend on what you've been doing (e.g. I've found that if I've had a real busy day shopping or something then the bub is real quiet).
Try not to worry and hopefully some of the other girls have a bit more advice for you than me ... specially those who are on their 2nd or more and have more experience O
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