Scared it's happening

So today the doctor prescribed me the medication I need to pass my sac. I was diagnosed with a blighted ovum. Which I'll be doing this evening. The one thing I'm scared of is I'll be traveling Sunday to New York and I heard because of the elevation I could get blood clots? Anyone heard of this? Is it dangerous for me to fly? Or will I be ok since it will be 2/3 days after? HELP