Sayang, at 7 weeks the scan image memang kadang-kadang tak clear sebab baby still sangat kecil, so it's actually quite normal, tapi since you're worried about it, better you check with your doctor or scan clinic to clarify what they saw, maybe they can do another one soon or explain what the unclear parts are. Jangan stress muna, most of the time it's just a positioning thing or the angle, tapi your doc will know best lah.