Help?!

I was suppose to have my period on the 20th or around the 20th and I haven't had it. I got sick yesterday morning I woke up feeling sick then not even ten minutes later got sick. I've been feeling nauseous tonight and my stomach is hard and after I eat I get bloated well if I am not bloated I still have a little belly and I am smaller size I cheer so I stay fit. And also I had a friend tell me that when you suck in you can see the outline of the baby well when I suck in there's still pudge. I'm scared and don't know what to do I am only 17. Please any help would be much thankful :)