I need advice

Jillian
My last period was June 28th... It's now August 2nd leaving me to have no period in July. I have taken 3 tests in the last week  Friday, sat and Sunday and all say negative. I don't want to keep wasting money on tests. Should I take another, or just wait? We have been trying for 8 months now so I'm super anxious and don't want to be let down.