Super confused!

Hey guys, so the last time I was sexually active was May 8th. Since then I have had TWO very normal and on time periods and no unusual symptoms of any kind. I was due for my period two days ago and so far there's still nothing. I'm not SUPER irregular, but I'm also not perfectly on schedule. I normally get crampy a week in advance and my boobs get sore. This time my cramps came a little later and my boobs hardly got tender at all. I could have sworn I started today and even had a tampon with the tiniest amount of blood on it, but then it stopped.. I highly doubt I'm pregnant, but the fact that I'm late is driving me crazy! Am I just psyching myself out and making matters worse? Or should I actually be concerned and go take a test? I'm just looking for some peace of mind! Thanks! :)