I need help with my feeling idk what’s up with me

Hi I am a 15 year old female. I have recently started acting and feeling strange which in a way I have never felt before. I don’t understand it either. All my life I have been a people pleaser. No matter what they did I would forgive them. I would talk to them like they didn’t just hurt me. I also never really said anything back to anybody even if they were in the wrong I always worried that I would hurt their feelings. Now I just feel weird when people do something to me. I don’t feel like crying anymore or I don’t get that feeling that I feel in my stomach. Instead It’s a feeling where I don’t feel sad or happy not even mad. I just don’t care no more. At the first time they do something to me I just don’t care I just don’t want to be around them or bothered I take them as a waste of time. I seem to give up on people and even though they are really special to me. It’s like disappointment but it’s much deeper than that. It’s a feeling like you don’t have nothing to lose anymore. I don’t even feel excited or happy anymore. I feel so tired but when I sleep it just doesn’t go away. Lately I been eating so much even if I’m skinny but it’s like I need it. But theirs times where I just don’t want to eat and I don’t. I last hours without eating even days. What can these feeling be ? Can anybody help me ?