idk if I'm pregnant

the reason why I post this is bc I'm only 16 and I think I'm pregnant.. I can't get some pregnancy test bc my parents and I'm not allowed to go anywhere without them... but I did a homemade pregnancy test (the baking soda) not even two weeks after I had sex and it said I wasn't pregnant.. but I just did one since it's been two weeks and it saying I am pregnant.. also idk if this can happen so soon but my stomach is hard and I can feel a tiny tiny ball on my right side of the stomach, and I've been eating evrything, heart burns, threw up once, I've been peeing every few minutes, I've been tired, craving stuff, and I really need someone's help please.