I hate not knowing

I think I may be pregnabt but only about a week and a half. My left side hurts on my back, like it did last time I was prego. My chest is sore and I feel very sick to my stomach and tired. It stresses me out not knowing if I am or not yet. I have to wait until march 15th to get my blood work done to confirm... Should I take the prenatal vitamins just in case?