MY CURRENT HAIR SITUATION.. HELP?

This is currently the colour of my hair. I know I should be posting a review or something today but I'm in a bit of a crisis.It doesn't look that bad in this photo but the ends of my hair haven't taken to the dye as much. It looks blotchy at the ends and my roots are quite bright. I'm going to run you through what I did and if any of you could help me, then please comment below. I should of took pictures of the process but I didn't think it would turn out this bad haha. I applied a pre-lightener on my hair and followed the instructions that came with the box. I washed it out my hair was ginger, which is what I expected. I then put a platinum blonde on next, washed it off and I looked like Draco Malfoy on the top of my head and ginger on the tips and freaked out. I couldn't find any toner in any of the shops around where I live to tone out the giner. So I thought it couldn't be any worse than it already is and got my bottle of conditioner and La Riche Directions semi permanent dye in Plum and mixed them together. I left it on for half and hour and washed it off, dried it and it looked blotchy. The next day I put mixed more conditioner and purple together and put it on but focusing on the blotchy ends and its still blotchy. The only thing I can think that makes it blotchy is because of the fact that even though my hair was blonde before I did this experiment, there were still red bits in my hair from before that the hairdresser couldn't get out. My question is, do any of you know how I can get this red out of my hair? The bleach in the hair dye obviously didn't do much to it. The hair colour I ideally want is like a white/silver blonde so that I can have pastel purple hair instead of this bright, blotchy mess. I know this is a rambley post and I hope that it makes sense but I do need help haha. Like I said, if you have any tips or know of any products to get white/silvery hair, please let me know below! Thank you guys!