Congratulations! Your dr can take blood and do a CBC and see if you have any difficencies that need to be addresses.
Fish oil, vit D, Calcium are the bare minimum. Consult nutrition specialist for your specific needs. Have you checked your iron levels? If low or borderline, might start iron supp early too coz you will run out of your iron storage very quickly as pregnancy progresses. BTW, I'm 5wk too. When is your due date? Mine on 8/14/2014. Congrats & good luck!
I suggest you do as your doctor recommends!