Only you can say whether she will cope in A&E.
In the meantime you need to do a huge sweep of your house. Knives, scissors, bleach, alcohol, nail scissors, razors, cutlery, remove glass, all medication, cords, string. Comb the whole house and lock it in the boot with your keys somewhere very safe.
We would be advising you to stay with her 247 - monitoring her. This will mean split shifts if you have someone with you, if not, make sure you sleep with her or near her with something to alert you if the bedroom door is opening.
It will require this level of care at this point, not forever, just for now.
Not unnerve you she obviously can not go out alone at all, not even in the garden.
Sellotape yourself to her until you have seen a doctor either this evening or tomorrow. They might prescribe medication, that can stabilise her, but it depends on her meds now and her age is a factor.
Stay calm op. Obviously you are going to be highly stressed but do what you can to lower the pressure with calming music and soothing routines.
If she likes massage, hugs, Indian head massage just try and regulate hee again, she may not wish for you to do this. Listening to bird song is known to lower stress levels.
Acknowledge that this must be a frightening time for her, that you are right next to her, and with you she is completely safe.
If you work, call in sick now, and plan to for the next few days, you need support too op. If you can reach out to any support networks you might have. We are here op. 247 on MN.