Pregnancy Symptoms...? Very Confused?

I have missed two periods, and there has been allot of weird things that have been happening to me. I used to gag constantly, but it has toned down a little bit. Whenever someone talks about velveeta cheese *gag* or I smell guacamole, i start dry heaving, until i eventually throw up. Every once in a while, I'll have this ache/twinge in my lower left stomach. It's not really painful, but I know it's there. Same with headaches. Except for one time, when i felt it coming on, so i fell asleep, but it woke me up in the middle of the night and it felt like something was stabbing me in the eye. I have a job, and I've noticed that I get winded, light headed, and dizzy easily. And I can't wear any extra clothing or stay inside for to long, or else I get over heated. I went out in negative degree weather in shorts and tank top and it felt amazing. Another thing I noticed, just came up about a week ago, that my are very sinsitive. My boyfriend touched them, and I fliched back because it hurt allot! And then he swore that he tasted milk, which I don't believe at all. My friend keeps telling me that I am, and that she knows the signs of pregnancy because she has a son. I took two home pregnancy tests, both negative, about one week after my missed period and then another a week after that... I also went to the doctors, and they made me do a piss test, when I asked them to do a blood test. They called me a few days later, and said it was negative. Is it possible that I might be pregnant, but it's to early to do tests? Or could I be getting false negatives? The doctors I went to work at Kaiser Permenente, if that makes a difference?