Nauseous but no puke or dizziness, am i pregnant?

hello. im 21. the other day me and my boyfriend were arguing, got over it, and he squeezed me real hard (hugged). usually nothing happens to me when he does that, but this time i felt like i was going to puke, and gagged, but nothing came out. the next day was fathers day, and i drank two beers. i was outside and they were barbecuing and the smell of charcoal made me nauseous i couldn't stand it, which was weird because the smell never bothered me. the next day i woke up to use the restroom. i tried to lay back down and out of nowhere i started feeling nauseous again. and its not like i got drunk the previous day because two beers is nothing for me. i was gaining weight before this because i was grubbing a lot, but now i feel a loss of appetite and have started losing a couple pounds. my mood is constantly changing. while i cooked the other day i feel nauseous, when im just watching tv i feel nauseous, and when im just laying i feel nauseous. and i don't ever puke. not so much dizzy just like stomach twisting type. i took a pregnancy test but it came out negative. and my stomach has been having a stinging pain. could i be pregnant? my boyfriend and i have protected sex, but ive had a couple of friends who used condoms but they busted.