I'm so confused

My period was due the 27th of April and it hasn't shown up and it's now the 1st of may ... I have cramps and feel as though it's trying to start but nothing. I've also taken about 5 pregnacy test one each day and they are clear negatives . Not sure what to do at this point wondering has this ever happened to anyone ( ps I'm not trying to conceive at this very moment just got caught in the moment and I'm in between birth controls )