Aww, first time twins, congrats mama, pero I totally get the worry! Please go see your OB soon para ma-confirm lahat, okay? At 5-6 weeks, sometimes the embryo ay hindi pa talaga visible sa ultrasound, pero kailangan ng doctor na mag-assess properly lalo na twins kayo. A few of my mum friends nag-worry din nang same thing, pero ang OB lang talaga ang makakasagot ng tama sa situation ninyo. Huwag maghintay, message your clinic today, peace of mind lang, bes!