Hi Laura Stanley,
Thanks for writing your query.
After reading your post, it seems that you have suffered only from soft tissue injury
of the scalp
with no internal brain injury
Headache will gradually disappear in few weeks time depending upon the severity of the attack.
If the pain is severe, you can take pain killer like Ibuprofen
one tablet twice a day after meals along with an antacid
. As about 3 weeks have passed, doing hot fomentation will be helpful in decreasing the pain.
If your problem persists or you develop some new symptoms, get yourself examined and investigated by a Neurosugeon.
I hope this is helpful to you.