You've probably mixed & mastered this one a bit too hot for SoundCloud and there's also some areas in the mix causing some harshness, especially with the vocals and the higher range frequencies.
SoundCloud normalizes your tracks at -14LUFS in both ways, if your Mix isn't loud enough it will be pushed up and if it's too hot it will be squashed down and the results is encoding distortion & clipping. If you take the original it's also mixed & mastered very hot and it's peaking in the red as well, that's heavy commercial music and it is what it is, but if you'd like to upload a still competitive track on SoundCloud, you can have your final Mix above the recommended -14LUFS but in that case lower down your Master from -2dB ( and even if you kept it at -14LUFS, it's recommended to then lower your Master from -1dB ).
Mixing wise, I would start by lowering down the kick and the vocals, lowering down the kick a tiny bit will create more space for the vocals level wise, so it will allow you to lower down & balance the vocals as well.
Then put an EQ on your Master at the last device in your chain and start by cutting some mud in the 200Hz, it should bring more clarity to the vocals and overall Mix and it will give you the opportunity to adjust the higher range. To me there's quite a lot of resonance in the 400Hz, 600Hz and 1K and above, mostly coming from the vocals and also that cymbal ride that you should also lower down in volume and tame the resonance with an EQ.
Playing around with a final EQ on your Master will give you a clue of the areas of the Mix than need some adjustments, by keeping that EQ on your Master and soloing each track it will help to know which channels are causing issues and you can then get back to individual channels to make more effective corrections, taming resonances with EQ, using a de-esser on the vocals and the cymbal ride, adjusting compression settings...etc.
So IMO, start by taking care of those levels, put that last EQ on the Master and cut some mud in the 200Hz area, then play around with low shelf curves in the above mentioned frequencies, low pass unwanted high frequencies as well and once you're happy with how it sounds, solo channels, engage/de-engage that final EQ on the Master and try to identify which channels are problematic and make corrections.
Once you're happy, try a new upload to SoundCloud, but keep in mind to reduce your Master by -1dB if close to the -14LUFS target and -2dB if you're above this.
For the rest it's a nice remix, won't judge too much about creativity here, TBH the original is probably less creative, hahaha those kind of pop charts are not really my cup of tea if I'm honest but putting this apart and trying to analyze the Mix and being objective, you did a good job IMO