Hello , I'm Only 15 And I Got Hit Hard

Hello , I'm only 15 and I got hit hard in the head when I slipped about 3 weeks ago. I've had these excruciating headaches and stiff neck . I've had blurry vision and my heart does this thing where it beats really hard for a couple of seconds , to the point where my body moves. My headaches come all of a sudden, but nonstop for the past 3 weeks . I've taken lots of medicine but none are helping. Should I see a doctor?