Frequent throbbing headache. Pl suggest!

Sir/Madam, my daughter Anusrita was affected with Covid on 13.1.22 (Mild, CT value-28). Within 7 days she became fine. Then on 27.01.22, while she was studying in her online class, at about 11.30am, she suddenly had vision problem to read characters in book (zigzag type). Then after 10mins, she suddenly started to feel throbbing headache at both sides of her head back side) which was starting from just behind the ear lobule at both sides. The headache was severe and lasted for 4.30hrs. Paracetamol not worked. Same throbbing pain recurred next another 2 days. As per our Doctor, Sibelium 5 started. But everyday she is having same pain but not lasting long time (1-2hrs, sometimes 15mins). Then Sibelium 5 increased to Sibelium 10. But problem is not solving. Also, while doing MRI, she couldn't stay because of the heavy sound of the machine. Within some times after starting the test, she got severe headache and couldn't do the test.She unable to tolerate sharp loud sounds at all. Pl suggest