I don't know anymore

So I should have started my period on the 17th and my husband and I have been trying to get pregnant for 2 1/2 years. I have thought so many times that I was pregnant but it's always been false hope. I'm scared to take a test and it be negative like all the other times. I have started ovulating again though and I have had a little bit of reddish brown color in my cm twice now. I know that I might just be late and start soon. Should I wait and see? And if so how long should I wait?