Is this why my hair falls off?

ok so this is part two to my hair falling question. so my hair is falling out in excess (i think) it falls out one at a time but so frequently as soon as one falls off another one comes off. i cant go 30 minutes without my hair falling out. i think its due to the weather because its almost fall my hair would normally fall out during that time. this same thing happened to me 2 years ago. i worried so much about it but then forgot about it and lernd- to deal with it and my hair didn't fall out as much. my hair always falls out a lot when i take a shower and brush my hair that's normal but when I'm sitting down or just walking around strands of hair coming out? so what should i do, i eat very healthy, i get my vitamins, i exercises everyday, i always eat. but i think the problem for me is stress, because there is no other way for this problem because its not hereditary and i think im a little to young to become bald im only 13. so what should i do?