Oo, marami sa amin ang nag-2D echo pa even late in the third trimester, kaya don't worry, it's actually pretty normal! One of my mum friends did hers at 32 weeks pa lang dahil lang nagmiss ng scheduled appointments, at ang OB niya ay totally okay lang about it, kaya siguro okay pa rin sa 29 weeks mo. The good news is the doctor can still check baby's position, size, and development nang maayos, so it's def worth doing especially if your OB is recommending it para sa peace of mind ninyo both. I'd just call their clinic to schedule ASAP so you don't stress about it, and trust your OB, they know what they're looking for at this stage na!