What Causes Dizziness And Nausea After A Head Injury?

I hit my head on saturday and right after, i had a headache and severe neck pain, i could not move my neck. I took some Aleve for my pain and went on with my day. 4 days later I was dizzy and had some blurred vision and still had neck pain and a headache that never went away. I went to urgent care and they said it was a concussion. Since then i have skipped school, gotten plenty of rest and fluids, limited time on my phone and watching tv which is what the doctor told me to do. Now, the dizziness has gotten worse, I can t walk without stumbling over and i can t close my eyes because i feel like I m spinning and getting nauseous and I still have a headache. What should I do?