First off what are your test results in ammonia,nitrite,nitrate,and ph, as popeye can be caused by poor water quality, first off do a water change on your tank, if the whitepsot looks like they have been sprinkled in salt yes it is whitespot, turn temp up to 30, add some salt if you have no scaless fish, add whitespot med.
You will have to cure the whitespot first, as popeye needs another med, an anti internal bacteria medicine.