Jonathan,
Sharp shooting pain is typical of some sort of nerve involvement and Gabapentin is the most common medication for that condition. The trick is to increase the dose to a level where you get some relief from the pain. Your doctor should have you on an increasing dose schedule. Do not make any changes by yourself. Talk to your doctor about an increase in your dose if you are still not getting any relief.
Also, Gabapentin does not work like the opoids, where you feel pain, take a tablet and the pain goes away. You have to build up your blood levels to a point where the Gabapentin will prevent the pain by blocking nerve impulses to the brain. Once the your blood levels are built up you must continue to take Gabapentin to maintain those levels.
Hopefully, after you more completely heal from your surgery the nerve involvement causing the pain will eventually resolve itself.