Always picking fights with my fiance and i don't know why! What should i do? I'm deployed?

I'm in the military and currently deployed to Kuwait. I love him with all of my heart, but it's so easy to piss me off. He is a 24/7 locksmith and sometimes when i call he doesn't answer the phone or he wants me to call him later. I don't feel important to him and the only way i can get attention is if i pick a fight with him...what should i do?