Hawksey. M/S is the WORST. With my first pregnancy i was working caring for ppl with intellectual disabilities and i had lots of trouble dealing with toileting/showering etc, but the worst was the soft serve meals - blerg!! I ended up telling my roster I was pg before i intended because i just couldn't hide my running to the loo to throw up a couple of times a shift! That and the fact that i was pretty useless at work really!!
This time I've been even worse with the sickness, and it was horrible during the worst weeks with a 2yo to look after. At least last time i had sick leave - this time, no such luck.
Anyway, if you can take the leave, do it. You might only need a couple of weeks and you'll be feeling more able to go to work. You do need to be taking care of yourself and your body at this time. And pushing yourself too hard is not doing any one any good.
You could ring your OB or GP and ask for a prescription as there are some medications that might work for you (i tried 3 lots and they didn't work for me, but i've heard they've done wonders for others).