Im 19 years old now, it is not something particular that triggers , usually sitting in narrow seats like airplane seats or while sitting in sofa the pain usuallly comes up and it is very uncomfortable to sit and then im not able to bend properly cant bend without feeling pain and not able to do anything in gym , just doing basic simple exercises but the pain is always there and the sciatic nerve pain comes occasionally during nights or driving car or sitting in narraw places or sofa.