Okay I tried posting this before, but something was royally messed up with the site for me....
Anyway, I have no clue what that pill is or does...But I don't think it'll harm the baby, simply because you're not taking it regularly and it was a one time thing. I would still call your dr just to make sure, they might want you to make an appointment and come in to have things looked at.
I drank one night when I was pregnnat, not knowing I was pregnant. I got super smashed and my baby turned out okay. When they asked me if I drank, I said yes and tehy ended up doing an u/s then for me. Along with the many other u/s I had because of my previous history with pregnancies. :) good luck to you hun!!