Wow, maybe she passed a blockage or got through eating something toxic. :O I'm glad she managed to pull through! Either way I'd consider getting her to a vet for a check up. At her age there's a lot that could be effecting her.
Since she's stable I'd be looking at;
Temperature
Poops (what are they like, how many, recently?)
Is she grooming (is she lifting her front paws while grooming?)
Look for teeth grinding (indication of pain)
Check ears, eyes nose for any discharge/redness/swelling
Look around her environment for any seriously toxic plants or chemicals (lead paint, noxious weeds, etc)
Check her diet (is she getting into chicken feed? eating a lot of alfalfa?)
Keeping her in tip top shape could help stop it from happening again
Since she's stable I'd be looking at;
Temperature
Poops (what are they like, how many, recently?)
Is she grooming (is she lifting her front paws while grooming?)
Look for teeth grinding (indication of pain)
Check ears, eyes nose for any discharge/redness/swelling
Look around her environment for any seriously toxic plants or chemicals (lead paint, noxious weeds, etc)
Check her diet (is she getting into chicken feed? eating a lot of alfalfa?)
Keeping her in tip top shape could help stop it from happening again