It's hard for them to evaluate anything over the phone. You should go see someone, even if it's just to say that everything is okay.
The head has a lot of blood. My coincidence, my dd on a preschool trip, fell and hit her head. The blood poured down. I come from a medical family and was a Flight Attendant so I whipped out a tissue to stop the bleeding asap. The teacher was right there with disinfectant and a bandaid. Today, she's fine.
Twice, we've had what I thought were innocent cuts which needed stiches. I couldn't see how deep they were.
Doctors in Germany are much less expensive than in the U.S. and they all speak English (part of their education). Take advantage because I've been in countries where they didn't speak English (or French, which we speak) and it's a pain.
Good luck and don't feel guilty. It happens to us all!