Pregnancy symptoms for two weeks, missed period, but negative Tests????

What does this mean? The last time I remember having a period was 6/25/18. I’m not 100% sure. I’ve been nauseous with headaches, food aversions, slight back pain, slight hip pain, but all my tests are negative. I posted one from earlier this week and a lot of people said they saw a faint posting but took two just now and both are negative? Is it too early for my period? How long should I wait to test again? Btw.. I have an ob appointment on 8/8 to see if I am pregnant and it’s just not showing up on the pregnancy tests. Maybe I am pregnant. I just have this gut feeling I am. Also I have a tiny bit of tingles in my boobs and butterflies constantly in my stomach. Even when it’s empty..