That's interesting, Mine was both head down around week 32 and it became one up and one down around week 34. I always sleep sideways because whenever i sleep face up i will feel breathless because baby pressing on the nerves or organs. During my pregnancy, i only keep worrying that my babies will be underweight and have to stay in NICU. So during pregnancy, i keep eating food high in protein and I have constantly have the urge to drink ice milo, ribenna and 100+ (ice/cold). I also eat durian to boost the babies weight. Don't know is it because of these food and drinks, my babies are born 2.8 and 2.9kg at week 36. I gained a total of 20kg and most of the weight gain are in the third trimester. So do not worry if you lose weight in the first trimester, it will go up in 2nd and 3rd trimester.