Pregnant?

My period is three days late, and last night i started getting an upset stomach. My mum and little sister also felt a bit ishy. Through out the night i started to feel a bit worse and at about 12:00 i vomitted. I vomitted another two times after that in a time span of about and hour. I started to think maybe it was something i ate or drank that day as two others in my family felt this way just not as bad. I also started to feel like since the pain and sickness was in my stomach/uptop that my body was trying to get rid of something maybe a bug because the third time I vomitted only the slightest thing came out.
Then this morning i started to think, if maybe i was pregnant. I looked up the symptoms and they do sound similar. So at this stage i have both possibilities in my mind. I would really appreciate any help to try and figure out wether i am or not and im starting to freak out. My period has been late before on multiple occasions but without vomitting, now with this added effect its got me worried.