Not enough folic acid?? Scaring myself!

Hi ladies! (Sorry if I am rambling) I am only at 4 weeks and 6 days along. I am overweight and something got me thinking maybe I need to be taking extra prenatals because of my weight. After googling a little I see that some overweight women are perscibed a lot more folic acid because there’s a risk of Spina Bifida associated with obese pregnancies. I am still waiting on a referral from my primary physician to see an ob and now I am worried! Is anyone taking extra folic acid? Should I go pic some up tomorrow before I can get into the doctor? Any advice on how to ease my mind?