Mood swings. Is this happening to me?

I have been suffering a very large depression and some times extreme happines for small things i m getting easily hurt by small things i started hating the persons whom i love alot i wanted to spend my time alone and i want to be alone suddenly i break into tears i feel myself as a loser i feel hopelessnes i felt like unlovable one i dont have any belief in love sometimes i just wanted to go the place where no one lives i lost control on myself nd i m getting extreme angry on small issues started behaving like a arrogant girl i m easily getting tense and at that time i m finding difficulty in breathing somtimes i feel like noone is there for me and i m alone sometimes i m doing the things which i dont want to do and regretting after doing that i became hopeless i feel like a loser i mbecoming weak day by day mentally idont know why is this happening to me