Suggest Treatment For Dizziness And Vomiting By A Child Post Injury

My family was at a Christmas party at my in-laws tonight. My 3-year old daughter was playing with the other kids. They were spinning around in a chair. One of the kids bumped into my daughter and she hit the back of her head on a shelf. She cried afterwards then seemed fine. The kids then started spinning her around in the chair and my daughter projectile vomited. I was in the bathroom when all this occurred and did not get to witness first-hand. I first was not worried as I figured my daughter was just dizzy from getting spun around and had no bump on her head. However she became more tired afterward and when she did get up 30 minutes later she was thirsty but vomited again before drinking anything. She is now resting with her head up in our recliner at home. Her pupils are reactive to light and she will open her eyes and respond when I try to wake her. She threw up basically watery bile two more times, once before leaving party and once on drive home and has not vomited since getting home about 1 hour ago. Concerned whether I should be seeking any further medical attention at this time or just continue to closely monitor her?