So, to be clear. She was bloated and some of her scales were pine-coning? Sorry to say but, it sounds like she had Dropsy. When you start seeing scales stick out it is usually to late.
Here is the info from the Diseases and Treatment sticky.
•Symptoms: Your betta will have a bloated belly and raised scales. They will look like a pine cone. This is usually a fatal disease caused by an internal bacterial infection resulting in internal organ failure but many have had success bringing fish back when treated quickly.
Early Symptoms: Swollen eyes (important), Gray belly (important), Clamped fins, Lethargy. If your fish has swollen eyes and a gray belly, I suggest that you treat it for Dropsy.
•Treatment: If you spot the early signs of Dropsy then treat him/her with ES at 1-2tsp/gal and Jungle’s Anti-Parasite pellets while performing 100% daily water changes. It helps to increase the temperature to 84*F. If he/she has begun Pineconning then do the full course as described below:
Performing daily 100% water changes. Increase the temperature to 84*F. Add 1-2 tsp/gal Epsom Salt. Use API General Cure OR API Erythromycin OR Maracyn II and/or Maracyn for best results. Feed something containing Metronidazole, for example, Jungle’s Anti-Parasite pellets. If caught early, Dropsy is curable.