What Is The Cause Of Swollen Labia After Hemorrhoid Tag Removal?

I recently had a old hemeroid tag removed last Friday through surgeryz. Starting Tuesday and getting worse through today, Thur, I now have swelling of the labia. It is not red. It is swollen so it is uncomfortable when I walk , sit, or wear underwear. What could cause this? The only medication I have taken is Vicodin or Ibrofen. I also take a cholestrol medication. I was recently told by my chiropractor to take i throid. I started sitting in a sitz bath of warm water. It helps with the irritation from the surgery and the swolleness. Thanks in advance.