It does sound like a pimple/boil. It may also be an infected sweat gland as well.
You don't mention how long it's been occurring. You are doing the right thing as far as warm compress. You may also want to try ibuprofen which will help with inflammation as well.
If it doesn't appear to be getting better, you may want to have your doctor take a look, you may need an antibiotic.
Hope this helps, If you need anything else please feel free to ask. If you found this helpful don’t forget to click the *accept* button!
