Dont worry. Lot of people have recovered photos after deleting them

What you need to do is find a Data recovery software from the Play Store

Wondershare Data Recovery is a useful app. If the picture was stored in SD card, MyJad Android Data Recovery can be helpful. Just try a few of these and you will recover your pic

It might take some time for the software to search all deleted items on your phone (new and old), if you remember the title, date of your pic, you can find it easily