How do I know if I am losing hair or not?

Have someone look. Tell them to piece through your hair and see if it looks thinned out. You may also notice more hair than usual on your pillow or brush or in the sink/ shower. If you grab a finger full of hair and give a bit of a non-painful tug, the hairs shouldn't come out easy, if there's any more than a few, your hair is falling out too easy.