Who am I?

Sometimes I get kind of depressed and cry at the smallest of things.  Then, I think, the only reason I'm upset is because hormones are telling me to be sad.  Then, I get even more upset because, darnit, if I'm going to be miserable I want it to be my own fault, not my body's.  Sometimes I feel like I'm a slave to my own body.  But then I think no, I'm a slave to living.  Anything that lives is deals with this.  Everything we do is decided by whether or not our body or surroundings are capable of that happening.  For example, if I want to be able to go underwater for a really long time I would have to make sure that I had a way to breath.  Another example is that I can't give blood because I weigh too little and even if I could give blood, I would pass out while doing so because of this primal instinct my body has to pass out. But, what becomes me and what is left as being my body?  Because I am completely dependent on my body.  You could say my consciousness is who I am, but my consciousness is changed by the way the chemicals in my body react.  So, if you just took out my consciousness, I don't think I would have any emotions or feelings.
What I really want to know is, who am I?

Saved a life

Today, I walked to my neighbor's house to take care of their dogs while they were gone.  I let the dogs out and went to feed their beta fish, seeing as I had not fed the poor fish in a day and a half.  I walked into the room to find that the fish tank had fallen over and there was almost no water left.  I quickly ran over and grabbed the fish tank.  I peered in to find that the fish was completely still, lying on some rocks.  No movement.  He however did not look dead, he still had the bright colors of a live fish.  I swished some water over to him, with the small hope that I would not have to tell my neighbors their fish was dead.  He started flopping around a bit.  I thought maybe it was just the water, but no, he was alive!  I ran over to the sink and put more water in.  Yeah, he's staying in the bathtub now, not precariously sat atop a pile of papers.  Now, I saved a life today, did you?