I Took A Pregnancy Test At Almost Three Weeks Pregnant

I took a pregnancy test at almost three weeks pregnant and it came out negative. My period came as normal and nothing else happened. Now I've missed my period twice, I'm nauseous, my stomach has gotten bigger (I'd be a little over two months now), I have heartburn, fatigue, crazy mood swings, and have abdominal discomfort. Not abdominal pain, just discomfort. Am I pregnant? Also, I can't get any medical care if I was because I am 16 and cannot afford it.