Hypos themselves won't harm the baby. As my doc just said to me, babies are very good parasites so they will get the needed glucose out of you no matter what you yourself are experiencing...
Regards stress, from what I recall from the pregnancy documentaries I've seen over the years only quite extended periods of high stress (with adrenaline and elevated cortisone levels) would be of worry.
And I think at 6 weeks the baby is only just starting to get anything from your blood stream anyway...? So your baby is fine, just try avoid the lows for your own sake (even tho the pregnancy hormones make it complicated at times) as they are horrible (and dangerous obviously if you fall!) x