info on photo in photos app: icon next to jpeg

there is an icon beside the jpeg label box on certain pictures saved in the photos library on my iphone 6s, like the contacts icon when there’s no saved image for the contact.. the label where it says jpeg has also displayed HEIF but there is an icon next to jpeg label only in a select few photos my girlfriend took, could it be they were sent to someone? can’t find details on that specific part of the info section in photos. any assistance is helpful.