Feeling Hopeless and Empty: My Struggle with Mental Health

this is my first post, not quite sure how this works but I'll give it a go because I just never feel heard or understood. I have so much going on atp I'm not sure where to start but I guess a good place would be this hopelessness I constantly feel.. just so empty or overwhelmed, there's no in between either I care too much or not at all. I have no real interests, no hobbies, no favorite anything.. music, movies or tv shows and am in a constant state of boredom.. I'm not living, just existing. I never was a crier but recently I cry for just about everything.. for good or bad things but mostly happy, for them.. then I get sad because I've never had moments like that and wish I knew what that happiness feels like. I'm in constant pain and nobody seems to understand just how bad I hurt, because I have good and bad days I can't plan ahead for anything because from one day to the next is different.. some days I feel I can do anything, others it hurts too much to do much at all. I'm tired of all of this, I just want to live a normal life of a person my age.