False negative?

Last period was April 12. I'm usually pretty regular and get my period to the day. I still haven't gotten it this month now I'm 4 days late. I had a miscarriage in February. My period came back to normal march and April. I took 3 tests all came out negative. 😢 anyone have a false negative before? After 3 negatives I've lost hope and told myself my period is just off and it'll come.