Although nervousness and shaking 'can' be an early sign of eclampsia, if she seems well within herself try not to worry too much. Also remember some discharge is normal for up to three weeks following the birth. I used to breed Yorkshire Terriers and the bitch would sometimes exhibit neurotic behaviour such as ripping up the bedding, my mentor had seen this happen before and told me not to worry too much....just make sure the whelping box was clean at all times....this seemed to calm my girl down.....and kill my washing machine!!!!! Be careful with Calcium supplements....they are not always easily absorbed by the bitch, if your worried though......Vets!!!!
Good luck
Lisa x