Prenatal Vitamins, TTC?

So me and my husband have been trying to conceive since my miscarriage in September.. With no luck, I thought maybe I was lucky this time around but my period showed it’s face. I use to have horrible long periods but after I lost my baby my periods have been like clock work and no more than 5 days, so that means me ovulating should be as well? It says I’m fertile from the 24th-30th. I ovulate on the 29th. What are the best days to try? I also recently purchased prenatal Vitamins, can I go head and start taking those or should I wait until a positive test?