On Android phone or tablet
Have you ever touched that bin by mistake when looking at a photo and then, maybe while being distracted, confirmed it? Here are a couple of methods to recover the photo on an Android phone or tablet, depending on how you deleted it.
Go to Google photos then select Library on the bottom row, then you should see a Bin option at the top of the screen. Look in this bin to find your photo. If it is here then select it and tap on the Restore option.
If the photo is not in the Google photos bin then it could be in the Recycle bin. Go to Gallery and tap the 3 lines at the bottom right then tap the recycle bin to see if your photo is here, again, select it and tap Restore.