Pain killers are the best solution for pain as long as you take it under the supervision of doctor and do not exceed safe limit. You should feel happy that your pain is of the type which is getting relieved with pain killers. As for the diagnosis, MRI
brain may also be helpful especially because your pain is present on the right side only. All pain killers are not same and discuss with your doctor about the worries that you have regarding long term use of these medications.