Hi, 6weeks preggy mom here

Jangan risau sangat ye sayang, it's actually quite common for the dating based on last period to be off, especially if your cycle was irregular or longer than usual, the doctor will usually re-date your pregnancy based on the scan instead of last period, so the gestational sac size becomes the more reliable guide at this stage. Gestational sac sahaja at early scan pun boleh jadi perfectly normal, because sometimes ovulation happened later than expected, so baby is just a little younger than what LMP suggested, do give it another week or two and scan again to see if fetal pole appears, InsyaAllah. For the sembelit and angin tu, ramai ibu-ibu alami benda sama in first trimester sebab hormone progesterone slows everything down, so do drink more air suam, makan buah tinggi fiber, and jalan-jalan ringan pun boleh help a lot. That said, every pregnancy is different, so please do discuss these concerns directly with your O&G doctor so they can monitor properly and give you the most accurate picture, you deserve proper peace of mind, bukan just overthinking sorang-sorang. Hang in there mama, you're doing great!