We're sorry your images aren't displaying in the Library. Without knowing exactly what's happening (for example, if's there's an error message) I can provide some helpful information such as this video: Uploading Images and Documents to Your Library [Video].
In addition, you can check the Recently Added folder to find your files. Both images and documents will display here:
Note there's a difference between images and documents. Accepted image formats include PNG, GIF or JPG. Accepted document formats include PDF, Word, Excel, or PowerPoint. Please let us know if you need any further assistance!