Possible concussion? Please help.?

So last Saturday I was at a playground. I was taking pictures of the fireworks, standing in front of a swing. My friend didn't notice me so he started swinging and before we knew it, he was kicking my head really hard. Ever since then I've been getting headaches that would come and go. After he kicked me, I lost balance but I regained it the next day. Might I have a minor concussion?