Bumps out are better than dents in.
If you weren't knocked out, remember what happened and are fully lucid and alert then you're probably going to be fine. Watch out for confusion, drowsiness, vomiting, alteration to your vision and hearing. Tell people in your household that you banged your head so that if any of the above develop they know to seek medical help for you.
Take paracetamol and try a cold cloth on the egg!