Ipod help?

so my ipod is bein really gayy. wen i go to turn my ipod on it just lke freezes on the apple screen thn goes black i had it chrging for lke 3 daus but its doin the same thing. then i sent it back and got it fixed but the second i plugged it in to my computer and put songs on it it did it again does anyone no why or how to fix thiss? thankss