Not exactly. Maybe he likes you and is complimenting your hair to get your attention. Maybe he likes you as a friend and likes your hair. Maybe he likes your hair but already had a crush on your, or...
Everyone differs. by how much that depends on if you mean number of hairs or overall mass which may be affected by both the number of hairs and the diameter of each individual hair.
Hair color has absolutely NOTHING to do with the NUMBER of hairs. No on can tell you how many hairs you have either, so I suggest you get to counting! :)