Yesterday, I got back from vacation and when I turned my ignition nothing happened.My car couldn't start nor did any the lights even turn on.I went and bought jumper cables and hooked it up to my roommates car. After doing this, it had a faint sounding crank but it I couldnt get it started. So I bought a new battery today and when I hooked it up, the battery fuse in the engine bay burned out. I went to Nissan and bought a new one for $16 and when I got back and put the fuse in, it immediately sparked and blew out again. Its really weird because this hasn't happened before. I even bought new terminals and installed them but that didn't help either. Any suggestions as to what I can do or what could be the problem????!