What color should I dye my hair now?

Hello, my name is jessie. I am 19. naturally my hair is a drty blonde color.my hair is really thin,like baby fine. I was into this thing where I kept that color,and added big mahogony highlights with lght blone highlights,layered it shorter,cut my bangs to prob my cheeks. I loved it. but thats all I was doing and people were getting bored,me too. so my friend asked to dye my hair,with those colors fading with box color. I was so scared.lol never used box color b 4. but it was cheaper,so I let her dye it this intense auburn color. at first I didnt like it. it was a purplish/redish color,but as I washed it more and more it was more reddish auburn. grew on me. but my hair grew out long,so I got it layered short again w my bangs to my cheeks again. now its like a faded red/blonde color. I have no idea what color to dye it now. not used to this stuff.lol bunch of suggestions for black or drk brown,but I dunno. then they think I should grow it out.its hard bc I dunno my skin color other then white w tan,lol im 5’4 with hazel eyes. Please Help!!!