Weird things

So it all started of when I was in school. Going to school I got back pain in the middle of my back and this lasted the whole 1st period. Then when going into my 2nd period the pain started to travel into my right ribs. The pain only hurt when I moved, then when I breathed then it just started doing really painful shooting/stabbing pains. It went down to my abdomen but also stayed in my ribs. Eventually I went to the office, they have me painkillers and it settled down (this happened 5 days ago on the Thursday). I went to the doctors the next day because I had a yeast infection so she also checked out my belly. To be honest she didn't really do a good check. She said my belly seemed fine. Every day after that I've been feeling like I want to throwup. I don't get pains in my stomach, I just feel sick. Yesterday I felt sick and had a headache, my heart rate was really fast but it went down a little. This morning I felt sick in the shower and felt like I was going to faint when i was in the kitchen. Right now I have a sore neck and pains in my back (left top side/shoulder) and sometimes a little pain in my left abdomen/hip and sore inside legs. 
I'm only 15 years old and this started 9 days before my period. My mum said it could be something to do with my period but I don't ever feel like this and I've never ever felt like this before. I'm really worried!
Any suggestions on what this could be? Please 😔😰x