Think I'm pregnant but I'm not sure please help?

I have had a mive headache all day and haven't eaten much at all. My stomach hurts really bad but I feel like if I eat I'm going to throw up. Me and my boyfriend have unprotected sometimes and I'm on birth control. I don't know if I'm pregnant. I started a new birth control this month so I don't know when I should have my period with this new stuff. But I'm starting to get nervous. Can someone help?