Trying to get pregnant

So me and my hubby had baby making sex lol. He ejaculated in me 3 times. Today is the 4th day of the day he did. And I'm feeling sick and smell of certain things is making me gag.. I took a pregnancy test and it came up negative but I'm not feeling myself at all.. This is my first baby in trying to conceive. I'm young and keep up with my body. Not to sure if it's just me or could I be pregnant and just not enough hormones to show I am? What do you guys think? Maybe I'm just really excited and really want to be a mom.