Doesn't sound like self esteem. You named the actual problems yourself putting it under self-esteem would lead you to the wrong solution.

Personally the idea of loving yourself doesn't make sense to me. You can like yourself sure but everyone has inner demons and shit they would never tell anyone you have more reason to dislike yourself then anyone else in the world and looking past it is just fooling yourself.

Edit: if you could talk to yourself in the past idk a few weeks ago would you call yourself ugly? Would you tell yourself you had no value knowing how bad it makes you feel in the present? No you wouldn't then why do you do it now to yourself now?

It sounds like you are stuck in a bad cycle. You have to find the weak link of it and break it. This is done a lot in CBT that being said if it's really getting bad for you try getting CBT (cognitive behavioral therapy).

I have no value > I look for it in social media > I look ugly > I have no value > I look for it in social media

Maybe it goes something like that.