Could this be from the medicine my mom is taking? ?

[Roman]

Well my mom takes not a lot of medicine but probably more than an average person and yesterday she felt dizzy and had a headache, today she stayed in bed all day because she didn't feel good, but her headache went away just now but she still feels weak and her stomache still hurts. Could this be from all the medicine she takes? They are prescribed by the way. What should we do? Thanks to anyone who helps