Heartbeats, bedrest is not necessary but if you are tired, just rest. I felt very tired during my OHSS period, hence the best position is to lay on bed, sleep when sleepy and get out from bed only for meals, water and toilet. Due to my severe bloatedness, 2-3 steps were very challenging and tiring. Be positive and keep your stress level as low as possible during 2ww. BTW, embryos will be safe inside even if you cough. I was thinking whether they were there in the past when there was changes to me. Haha... nurse always say we gals are over reacting over some small matters. But she can't understand it's also our first time and especially we know the embryos are inside us.
Noy, you can rinse your throat with salt water every morning after brushing your teeth if you are in the initial stage.