How can i love myself? (be happier)?

I've been feeling really depressed lately, and i've self harmed. I feel like i'm worthless and sh1t, i don't know how to love myself more and be happier about myself. i get compliments of how pretty and beautiful i am, but i don't seem to take it in?.. i guess due to my childhood (age-6-12) i was an ugly child and had really bad self-esteem... i'm 16 now, but i still feel the same? any advice please? i don't want to feel worthless (and it's not hormones because i've been feeling like this so years...)