I think it would be beneficial for you to tell *someone* how you're feeling. It doesn't need to be your mom or your dad if that frightens you too much (although I'm sure they would react better than you imagine), but I absolutely think that it's essential you find someone you feel comfortable enough with to be totally and completely honest with in regards to how you've been feeling. You need to get that weight off of your shoulders.

It does sound normal to me, my most emotional years were my late teens. I cried a lot, struggled with anorexia and self-confidence, and obsessed about what others thought of me/how they felt about me (specifically my boyfriend at the time). Having a support structure is vital, please, please, please do not keep this all to yourself.