Very Late

My period is really late...I skipped last month all together and my next start date is the 30th of August. I've taken about 5 different pregnancy tests on different days throughout this time and they all say negative. Very clearly negative. Weight and diet are all the same. I'm a little stressed that I haven't gotten my period yet but nothing other than that. My boyfriend and I always use protection and we haven't had any "oopsies". Thoughts? Suggestions? Anyone experience the same thing?