No thuds yet, graciously.
The spotting stopped fairly quickly and has not returned since. I debated calling my doctor, for reassurance, of course, but I decided against it, mostly because I know that there is really nothing she or anyone can DO right now. It is far too early for delivery and, sadly, there is little else to be done. Second trimester spotting is usually a result of something affecting the placenta and all we can really do is wait and hope. Wait and hope.
I suppose that 24 hours of serenity is better than nothing at all.
In the meantime, a huge thank you for your supportive comments. I am hanging on dearly to the knowledge that this could turn out just fine.