... get him a qt larger tank. Half a pint is waaaay to small, even for a qt tank. For a qt/hospital tank maybe 1/2 a gallon to 1 gallon large with 100% water changes daily is good.
IMO, if it's not that bad, stick him back into his tank. A warmer and larger place will make it easier to keep the water pristine and good for him to heal. If you could describe what his tank is like using the form that ShinyBetta posted, that'd be helpful too. :)
IMO, clean water and either one to two teaspoons of epsom salt or aquarium salt per gallon might do him more good than betta fix.