The symptoms you report could be from the knock she has taken from the head injury
. Given her previous history of head injury and the knowledge of the tests she has to do when being examined in hospital, it sounds as if at the moment she is OK. However, with the initial symptoms being non-specific it is very difficult to rule out any underlying severe injury to the brain. So the best advice is to visit the ER closest to you before she has the collapse you fear about!
Feeling tired in not "normal" but it is very difficult to explain whether the tiredness
will get better or if it is due to something innocuous or serious.
Given your constraint with accessing medical care, it is very important to have someone with her all the time for the next 48-72 hours to look for the warning signs including excessive sleepiness and the others you mention. I would again advise you that the safest option is to go to the ER and have her checked out even if that means the same physical examination and reassurance.
While there is no specific contraindication to texting or internet use, it may be much better for her to rest now and save here energy for these activities later when she has recovered. Finally, anything in moderation is OK and any activity, however innocuous done in excess could lead to problems!
Sorry that I cant give you more specific advice. Hope this helps.