Hey Mako, I'm sorry you came away from your apt worried. But a good strong heart beat is always good news. Hope you're able to keep the stress levels down as you wait for Monday - it's only natural you'd be feeling anxious though.
And I totally agree you should talk to work. I understand if you feel obligated to see out your time, but if they havn't found someone else that's really their fault and it's them that's potentially leaving students in the lurch, not you - ykwim? If my OB said that to me, I would not be going into work again... Err, sorry, sounds like I'm telling you what to do - just concerned for you is all.
Take it easy, ok?

Oh, and have fun with the swab