Emotional instability

Hello , i hope someone among u know what i am going through! So here :- since from childhood i have been unable to feel hurt whenever something bad happened to people i knew! Like my bro had an accident and was serious could die i got a call and couldn't feel anything i didn't care ! Instead i was smiling , same happened with my sister she had to admitted in hospital few days ago lying unconscious and i was smiling even tho she could die ! I couldn't feel or wasn't a bit scared that i might lose her ! I want to feel , tho i do feel but very late when i mess up everything then i regret!! I don't know how to describe! My mom works hard but i don't care ! I want to care because i have lost so much due to this problem! I laugh at my own demise too from inside there is feeling of happiness that tells makes me happy losing people or things , i failed my exams and i wanted it i don't know y i wanted that ! And after i lose i regret so much it's like I don't value things when i have them but always always becomes sad after losing them ! Lost my ex gf too cuz i didn't want her at that time i lost feelings but when she is gone it hurts so much that i want her back ! What is wrong with me please if anyone can help me. I want to be Normal too , i never gave my 100% in anything i just start things and leave them in middle! I have lot more to tell ;