My hair

I've always loved my hair, and everyone else has always loved my hair. But I have encountered a problem. It keeps falling out, and I don't know why. We are supposed to lose about 20 hairs a day, according to my cosmetologist friend, and I've been losing A LOT more than that. I don't know if it's stress, my health, or both, but it frightens me. Do any of you have any solutions and/or tips? I'd appreciate it