Hi celaeno :0
Since swim bladder problems could be caused by either an injury or an infection, the extra handling and netting involved might be more trouble than it's worth. Your best bet might be to isolate it and wait to see what happens. If it's bacterial in origin, Erythromycin is an appropriate medicine to use.
For future reference, salt can be very effective when a fish is suffering from a bacterial infection such as finrot. It cleans the wound out and then the antibiotic you will have put in the water can more easily heal it.
I use about one tsp. of aquarium salt per two cups of water, in a container large enough to hold the fish. Dissolve the salt well before adding the fish so it doesn't eat any. Add the fish and leave it for between 5 and 20 minutes, taking it out earlier if the fish passes out and rolls over. Don't worry-- it will come to when you get it back into its tank. Repeat the process up to 6 times a day until healing is well on its way.
I hope your fish improves quickly.