HELP FREAKING OUT!!! Need some advice plz!!!

Ok so I was meant to have my period 2 days again and it hasn’t come yet I’m only 16 and I have a boyfriend and we are sexually Active like 3 times a week sometime and we have sex without a condom sometimes and things I’m on the depo needle less then a month ago I started it and I forgot u have to wait a month for it to go properly in your body and I’m freaking out my boobs hurt and I have bad lower back pain and I have put on some weight and the smell of some food makes me want to vomit what do I do?? Plz