Your profile says she's 94. I'm not sure I would put her through any medical tests or exams that are too stressful or invasive. Maybe it's time to call in hospice...?
Don't force her to do anything. If this is new - is she sleeping much more than usual? - call her doctor and report it.
Meanwhile continue to encourage her to get up (suggest helping her to get to the bathroom, for example), offer her small snacks or meals that you know she likes, and make sure there is always a drink within her reach. Try to be cheerful and positive with her, even though I'm sure you must be worried.
When was the last time she was checked by her doctor?
A big change like this should be discussed with her doctor, it could be a urinary tract infection or something treatable that can cause needless suffering if not treated.
It could also be the end for her, but you should contact her doctor to help you with this situation.
Meanwhile continue to encourage her to get up (suggest helping her to get to the bathroom, for example), offer her small snacks or meals that you know she likes, and make sure there is always a drink within her reach. Try to be cheerful and positive with her, even though I'm sure you must be worried.
How often are you able to check in on her?
A big change like this should be discussed with her doctor, it could be a urinary tract infection or something treatable that can cause needless suffering if not treated.
It could also be the end for her, but you should contact her doctor to help you with this situation.