Hooked up car cd player and it doesnt work.?

So I bought a new cd player and when I took out my old the wire plugin didn't match my new one. So I looked at each set of wires and I cut off the old plugin. I grounded the black wire with the metal piece to a screw inside my dash. Then I split the same wires of each set and twisted them together and then used electrical tape to cover them. There were some extra cords but I had no where to hook them up so I wrapped them up so they wouldn't just be open inside of the dash. I then plugged in the power (or antenna) not sure which one it was but it fit my new cd player as well. I then put my dash back together and screw in and plug back in everything I had messed with in order to get to my cd player. I turn my car on to see if my cd player works and I here it make a noise (the cd player itself) but it didn't come on. No lights, no sound, nothing. What did I do wrong? How do I make it work??