need advise please

I might be pregnant, but I’m not sure. For the past few months, i’ve been alittle late on my periods. My last period was feb 2, and i think that i’m having signs of pregnancy….. but i’ve never been pregnant, so i don’t really know.
(I’ve been sexually active… without protection.) I told my friend about everything that’s been happening, but she doesn’t think I’m pregnant, she thinks that it’s just signs of my period. (she told mye that pregnancy symptoms can be the same as signs of your period) the first thing that happened was I woke up at like 3 a.m. with heartburn so bad that I could barely stand it. Then I started throwing up. I was sick from then until alittle bit after noon. The rest of the day, I was REALLY naseous. I couldn’t even think about food. (my friend told my that it wasn’t morning sickness. she said that with morning sickness, you throw up and then you feel better.) And most days, I’m really tired during the day, but i can’t sleep at night. sometimes, i’ll stay up until around 5 a.m. because i can’t sleep. And i have odd food cravings. (Things that I’ve never really craved before, like pineapples, and pickles, and lemon flavored food.)
And my breast are starting to get bigger, but the aren’t really sore. I have know idea what else it could be, but friend (she is pregnant with her 2nd child) doesn’t think i’m pregnant. Please give me advise on what you think. I would be VERY grateful!