Yes, you need to color your roots. Here is what happened - when you bleached, your roots lifted much lighter because they were virgin hair and your mid-lengths and ends had the hair color to lift through. You need to find permanent hair color that matches your ends and color just your roots, leave it on for the full time to make sure you get good coverage. You can pull it through your ends the last 5 or so minutes to blend if you like but they are over-processed at this point (I would bet) so they will have a tendency to grab the color. You can even dampen your ends before you pull the color through and that will help with that a bit.