Oh dear, sending you a big hug, a few of us in my mum circle have been through this and I know how scary that 8-week scan can be when they only see the gestational sac and nothing else. One thing a few of us noticed is that doctors sometimes use the word "possible" because they want to rescan in about a week or two before confirming anything, so try not to spiral just yet. The nausea and pregnancy symptoms can still be very present even with a blighted ovum, which feels so cruel and confusing, but it does not necessarily mean the diagnosis is wrong either. One of my mum friends went through a confirmed blighted ovum at 8 weeks, had a D&C, and was pregnant again within a few months with a healthy baby, so please know there is real hope ahead even if this pregnancy does not continue. Of course, every situation is different, so do have a thorough conversation with your O&G specialist who knows your full history, they are really the best person to guide you on next steps and timing.