What do you do if you have a severe migraine occasionally and already have past trauma to the brain from childhood and have had side affects to nsaids?

See your neurologist: There are many medications that can be used both for prophylaxis and treatment of migraines that are not non-steroidal anti-inflammatory agents; notwithstanding, there are a myriad of different type of NSAIDs as well, so even within that category there are options. A neurologist can help determine a plan to assist you in control of these headaches within the bounds of these historical aspects.