TTC, I'm using the charting method this month but i'm confused can you help me?

If you are just starting out charting/using opk's I would say go ahead and test again this evening, it can't hurt. When you first start out you are basically trying to get an idea of your cycles, so after the first month or two of charting hopefully your cycles will be predictable enough that you won't need to use opk's for as long each cycle. I usually get my 1st positive opk 1 day prior to o day, but it is different for each woman. So just to be safe so you don't miss it, I would say yes go ahead and test again tonight. Best of luck to you!!!