Thanks for your question on Healthcare Magic.
I can understand your concern. 
By your history and description, possibility of 
migraine is more likely. 
I don't think she is having 
Vertigo because she is not having giddiness or spinning head. 
Better to 
consult neurologist for the diagnosis of migraine. 
If migraine is the cause then she will mostly improve with all these. 
1. Avoid stress and tension, be relax and calm.
2. Drink plenty of fluids orally. Avoid Fasting and take meals timely.
3. Start 
propranolol and 
flunarizine combination at night..
4. Avoid excessive sun exposure.
Don't worry, she will be alright with all these. 
Hope I have solved your query. I will be happy to help you further. Wishing good health to your mother. Thanks.