Low blood pressure is common in thalassemia and it is thought to have some cardio-protective effect in thal minor, resulting in less heart disease among minors. Outside of medications to raise BP, you should always stay well hydrated as the fluid volume is instrumental in maintaining blood pressure. There are no restrictions on salt intake when your BP is low, so try some salty foods when you feel that it is low. This really does pick the BP up quickly. I doubt you're going to get up close to normal but you should be able to raise it some.
As far as the personality traits, I think that's all that is. I recognize some similar features in myself and realize that my patience and tolerance are dependent on constant conscious efforts, and slipping is quite easy. In today's world, who can blame us when our patience runs thin?