My 16 Year Old Son Received A Bad Concussion Playing

My 16 year old son received a bad concussion playing football 2 weeks ago. He has had symptoms this entire time. Headaches, dizziness, inability to study or remember for tests. Now today he got a bad headache and out of nowhere he had a bad nosebleed. He was very dizzy after the nosebleeding stopped. Should we seek medical attention? Could this be from the concussion?