I don't know how long it will be before she feels better. I would reread the postop page, especially the info from Talishan's post (which is on that page).
It has been almost three months now and she is as good as new. The first three days were rough. She came home and was like a little lump, probably still a little loopy from the surgery, not moving or doing much. That was hard but I continually offered her hay and veggies, she didn't much care for critical care. She did eat though so that was good. Naturally her weight dropped, and she lost a little more in the day or 2 after but then we maintained and now she is actually at her heaviest since I have had her. Pain medicine was essential, she was taking matacam 1 time every 24 hours, but she was still in pain, so the vet said once every 12 was fine as long as she was still eating drinking good. We used the metacam for about 4 days I think. She was separated from her cagemates in a 1x2 at one end, but by exactly one week she was freaking out and wanted to be back with them! Her incision healed great, you can hardly even see the scar on her tummy now. One thing I was unprepared for was that there was a slight amount of blood in her urine for about 3 days after. The vet said that was ok, but if it increased or continued any longer then it did to bring her back.
To offer my 2 cents to anyone reading this and considering options for cysts. . . Most important would be to find a vet that has experience doing surgery on small animals. Then you need to consider the piggies current health and if they can handle an invasive procedure. And finally, you need to be able to do good post op care, including enough pain medicine. We were really lucky (though I did not sleep much the first 2 nights!) as I am home a lot, and my family was very understanding of me camping out by the pigs for days.