panicking !!

Heaven
Hey girlies, so I'm in a bit of a pickle. It shows that I didn't get my period last month. I don't know if I forgot to write it in or I really missed it and I'm totally freaking out. My boyfriend and I don't remember me talking about my period last month. Should I take a test or wait for this months period?? I normally start around the 20th. What should I do?