Congratulations on your first cleanse! At 10 days, you've done a great job. Have you read the "Stages of Detox" post in the FAQs? If not, that info could help you decide if you want to continue or not.
From what I've experienced/read on this forum, it's rare for the tongue to clear with a 10 day cleanse. There are even people who've gone 40 days without their tongue clearing. I'm on the 15th day of my 11th cleanse in two years, and this is the first cleanse I've done where my tongue wasn't completely gross the whole time. Point being, the state of your tongue needn't be a deciding factor. :^)
If you want to continue and the sore bum is your only reason for stopping, start using baby wipes instead of toilet paper. That should help.
All the best,