Am I pregnant ?

I’ve been experiencing a constant state of nausea, heartburn, and headaches. I assumed it would be too early for any of these things to be happening if I were pregnant. Today is the first day of me missing my period. I took a pregnancy test this morning and felt like I saw a very very faint line. My husband says the tests kind of show you where the line is supposed to be before you pee so my test was definitely negative. I really want to be pregnant but I hope my mind wasn’t playing tricks on me. I just took another test and I didn’t see anything. My heart is just sinking right now. If I’m not pregnant, can someone tell me what might be going on?