I see that the filters that you had on your photos have been removed. I use filters on my photos often myself. I can understand the confusion, and I'd be happy to help.
If you were not using iCloud Photo Library for your photos, you can restore from you last backup. This link will show you how to restore from a backup if needed:
Restore your iPhone, iPad, or iPod touch from a backup
If you were using iCloud Photo Library, you'd want to reach out to Apple Support. You can reach them by using the following link:
Contact Apple Support
Thank you for using Apple Support Communities.
Have a great day!