Will my baby have spina bifida?

I am 5 weeks, 3 days pregnant and I only found out about an hour ago that I am expecting my second baby. I'm absolutely elated, but now the fear that I'm doing something wrong is setting in. I don't have any money until Thursday for prenatals (I wasn't trying to get preggers) and I've been eating all the food I can with possible amounts of folic acid in it. I'm super paranoid that I'm going to cause spina bifida or something just as bad because I haven't been taking vitamins. Will my baby be ok???