I'm so sorry! A great safety feature on the iPhone is that deleted pictures remain in the "Recently Deleted" view for 30 days before they are removed permanently. This safety feature can be defeated, though, by choosing to prematurely delete pictures from the "Recently Deleted" view. If you use iCloud Photos, then that "synchronizes" its Photos Library with the phone, so what you see on the phone is what is at iCloud. iCloud Photos doesn't keep pictures in "Recently Deleted" any longer than the phone does.
The link that razmee209 gave has a lot of suggestions, but they basically say to look in Recently Deleted and in Hidden, which may not apply to you. Unfortunately, If you don't keep your own backups to an external drive, then there really isn't any place else to look.