I'm no doctor, but I've seen hundreds of these type of injuries.
Firstly, what everyone says above is correct, what you and your eldest are experiencing are completely normal. Ibuprofen for you (Sqad will advise correct dosage, otherwise just read the packet), plus cold compress.
Secondly, I think it very likely you will feel WORSE tomorrow. That is also quite normal. It is worth seeing a doc, even if he advises over the counter anti-imflammatories. If it turns out to be worse, you might need phsyio which you might get the other side to pay for.
Thirdly, try not to dwell on the "what if" and instead think of the "what did".