Thank you for your question. These sorts of trauma with kids are unfortunately quite common, as most of us with kids can attest. The real crux of your question however is with regards to what symptoms need to be seen by a doctor
and which will resolve by themselves over time. In general, if you have a question about a symptom, you should at least call or speak with your doctor to describe the problem and determine if you need to be seen. With specific regards to head trauma, there are some keys. Any persistent changes to any of the nerves of your head and neck would be a sign that you need to see a doctor (such as vision changes, not able to move your tongue, not able to feel an area, etc). Other signs such as large trauma to the skin that may need suture also need to be seen. Loss of consciousness or persistent pain that is out of proportion to the injury
are also things that should be seen by a doctor. There are many other symptoms that need to be evaluated by a doctor, but these are a few of the common ones. Please speak with your doctor.