Hello from JustAnswer.
The most concerning symptoms w the incoherence and confusion, which are changes in mental status. Nausea, vomiting, and diarrhea are most likely due to a viral infection. It is common for a viral infection to cause her to have poor colour and wanting to sleep.
If she is having mental status changes, then it would be better for her to be seen. It could be related to another stroke, but it also could be related to an acute infection, or a complication of an acute infection, such as dehydration or electrolyte abnormalities.
If the mental status changes were only transient when she woke the first time, but is now having a normal mental status along with the symptoms that are more likely a viral infection, then it would be fine to manage this at home as a viral infection. But if she is having any further mental status changes or the mental status changes recur, then it would be better for her to be seen at the hospital emergently.
If I can provide any additional information, please let me know.
Yes, as long as there are no further mental status changes, it would be appropriate to encourage fluids and to let her rest. If she sleeps all the time, it would be difficult to encourage fluids, nor can you monitor mental status, so if she does not awaken on her own, it would be appropriate to wake her every couple hours to encourage fluids and see how she is doing.