Cactus stay positive, like you said that there is really nothing u can do but hope for the best. besides, it's still within range. your bb big so everything big, it's only natural mah. (given your measurement, think ur bb is on the big side)
When I had my detailed scan for my #1, one of the ventricular tube,( somewhere in the bb head) was out of range, too big. It was an indication of abnormality so asked me to do amnio. Mind u I was only 27 then. worried me sick, cried like mad and wait for soooo long for results (1 mth) hellish for the whole entire month! after that turn out ok. Really thank GOd man. This time round, I've learnt to take it easy. more like numb already.