I'm only 16 so what is making my hair fall out SO MUCH?

I don't do anything awful to my hair. I straighten it occasionally and I've only dyed the bottom half of my hair red with Splat hair dye. The only parts of my hair that i flat iron on almost a daily basis are my bangs. I haven't changed my diet or anything and I'm not exactly too stressed about school. I just don't know what the problem is and I'm just tired of my hair shedding in inexcusable amounts. I use a wide toothed brush after I wash it to brush out the tangles and I'm always gentle, like I'm treating a new born baby, and still my hair just keeps on falling out and falling out. It's so ridiculous. What am I supposed to do? Any treatments or remedies? Someone just help please. I fear that I might be going bald.