I have been depressed for a really long time i need to know

i have had depression issues since i was in high school and also around that time a weird occurance started happening. I am always depressed but i dont ever show it and i almost feel like nobody knows who i really am, i dont even know nemore. the other night i was trying to go to sleep and i just felt really bad i had horrible thoughts in my head about my life and everything about it and it was unrelentingly negative. I literally started to feel it in my stomach just how much it hurt how bad everything was and i tried to just shake it off get it out of my head and it wasn't working i am afraid to tell neone how i really feel on a daily basis which is like no one cares and i feel like nobody likes me even though im pretty sure its not true i can't help but to feel awkward in conversation. Also occasionally i will start to feel really weak and then my hearing and vision goes away and i just pretty much can't move or speak idk if its an anxiety thing or what but it has happened a couple time over the years but i have had this happen twice already this year and these are the closest it has ever occured together. i dont know what is wrong with me i dont know if i am just feeling sorry for myself or what no matter what i do these feelings dont go away i just want to be happy again i need to know what's wrong with me if anyone can help please do thnx